# CVE-2026-50256: Xorg-x11-server: xorg-x11-server-xwayland: xorg-x11-server: stack buffer overflow in font alias resolution due to libxfont2 name length mismatch

Status: published. Published: 2026-06-05. Updated: 2026-11-04.

A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland. A mismatch between the X server and the libXfont2 library's maximum font name length can cause a stack buffer overflow during font alias resolution. The server allocates a 256 byte stack buffer but libXfont2's alias target name length is 1024 bytes. A font alias name between 257 and 1023 bytes causes the X server to copy that name into the undersized stack buffer without further checks. This may be used to crash the server, or for privilege escalation if the X server runs as root.

## Remediation

- workaround: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability. (source: CNA: redhat)
- fix: RHSA-2026:49519: Red Hat Enterprise Linux Server -EXTENSION(v. 6 ELS-EXTENSION), Red Hat Enterprise Linux Server Optional -EXTENSION (v. 6 ELS -EXTENSION)

RHSA-2026:46473: Red Hat Enterprise Linux Server (v. 7 ELS), Red Hat Enterprise Linux Server Optional (v. 7 ELS)

RHSA-2026:36083: Red Hat Enterprise Linux Server (v. 7 ELS), Red Hat Enterprise Linux Server Optional (v. 7 ELS)

RHSA-2026:36798: Red Hat Enterprise Linux AppStream EUS (v. 10.0), Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0)

RHSA-2026:26566: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)

RHSA-2026:28923: Red Hat Enterprise Linux AppStream (v. 8)

RHSA-2026:26709: Red Hat Enterprise Linux AppStream (v. 8), Red Hat Enterprise Linux CRB (v. 8)

RHSA-2026:26562: Red Hat Enterprise Linux AppStream (v. 8)

RHSA-2026:46382: Red Hat Enterprise Linux AppStream AUS (v.8.4), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4)

RHSA-2026:36792: Red Hat Enterprise Linux AppStream AUS (v.8.4), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4)

RHSA-2026:46460: Red Hat Enterprise Linux AppStream AUS (v.8.6), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)

RHSA-2026:36791: Red Hat Enterprise Linux AppStream AUS (v.8.6), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)

RHSA-2026:38810: Red Hat Enterprise Linux AppStream AUS (v.8.6), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)

RHSA-2026:46385: Red Hat Enterprise Linux AppStream E4S (v.8.8), Red Hat Enterprise Linux AppStream TUS (v.8.8)

RHSA-2026:36768: Red Hat Enterprise Linux AppStream E4S (v.8.8), Red Hat Enterprise Linux AppStream TUS (v.8.8)

RHSA-2026:38502: Red Hat Enterprise Linux AppStream E4S (v.8.8), Red Hat Enterprise Linux AppStream TUS (v.8.8)

RHSA-2026:46377: Red Hat Enterprise Linux AppStream E4S (v.9.2)

RHSA-2026:36086: Red Hat Enterprise Linux AppStream E4S (v.9.2)

RHSA-2026:36633: Red Hat Enterprise Linux AppStream E4S (v.9.2)

RHSA-2026:46456: Red Hat Enterprise Linux AppStream E4S (v.9.4)

RHSA-2026:36087: Red Hat Enterprise Linux AppStream E4S (v.9.4)

RHSA-2026:36632: Red Hat Enterprise Linux AppStream E4S (v.9.4)

RHSA-2026:46392: Red Hat Enterprise Linux AppStream EUS (v.9.6)

RHSA-2026:36085: Red Hat CodeReady Linux Builder EUS (v.9.6), Red Hat Enterprise Linux AppStream EUS (v.9.6)

RHSA-2026:36634: Red Hat CodeReady Linux Builder EUS (v.9.6), Red Hat Enterprise Linux AppStream EUS (v.9.6)

RHSA-2026:29844: Red Hat Enterprise Linux AppStream (v. 9)

RHSA-2026:26610: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)

RHSA-2026:26590: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) (source: ADP: redhat-SADP)
- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: secalert@redhat.com) — https://gitlab.freedesktop.org/xorg/xserver/-/commit/bb5158f962dc935e58ef8b4b5fcb31be201a6e07

## Affected products and versions

- Red Hat / Red Hat Enterprise Linux 10 (xorg-x11-server-Xwayland): ≥ 0:24.1.9-4.el10_2.2; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 10.0 Extended Update Support (xorg-x11-server-Xwayland): ≥ 0:24.1.5-6.el10_0.1; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 6 Extended Lifecycle Support  - EXTENSION (tigervnc): ≥ 0:1.1.0-25.el6_10.18; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 7 Extended Lifecycle Support (xorg-x11-server): ≥ 0:1.20.4-35.el7_9; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 7 Extended Lifecycle Support (tigervnc): ≥ 0:1.8.0-36.el7_9.5; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8 (xorg-x11-server-Xwayland): ≥ 0:21.1.3-20.el8_10.2; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8 (xorg-x11-server): ≥ 0:1.20.11-28.el8_10.2; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8 (tigervnc): ≥ 0:1.15.0-10.el8_10; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support (xorg-x11-server): ≥ 0:1.20.10-5.el8_4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support (tigervnc): ≥ 0:1.11.0-8.el8_4.16; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On (xorg-x11-server): ≥ 0:1.20.10-5.el8_4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On (tigervnc): ≥ 0:1.11.0-8.el8_4.16; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support (xorg-x11-server): ≥ 0:1.20.11-8.el8_6; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support (xorg-x11-server-Xwayland): ≥ 0:21.1.3-2.el8_6.7; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support (tigervnc): ≥ 0:1.12.0-6.el8_6.18; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On (xorg-x11-server): ≥ 0:1.20.11-8.el8_6; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On (xorg-x11-server-Xwayland): ≥ 0:21.1.3-2.el8_6.7; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On (tigervnc): ≥ 0:1.12.0-6.el8_6.18; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.8 Telecommunications Update Service (xorg-x11-server): ≥ 0:1.20.11-19.el8_8; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.8 Telecommunications Update Service (xorg-x11-server-Xwayland): ≥ 0:21.1.3-13.el8_8.1; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.8 Telecommunications Update Service (tigervnc): ≥ 0:1.12.0-15.el8_8.18; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions (xorg-x11-server): ≥ 0:1.20.11-19.el8_8; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions (xorg-x11-server-Xwayland): ≥ 0:21.1.3-13.el8_8.1; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions (tigervnc): ≥ 0:1.12.0-15.el8_8.18; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9 (xorg-x11-server-Xwayland): ≥ 0:24.1.9-4.el9_8.2; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9 (xorg-x11-server): ≥ 0:1.20.11-34.el9_8.2; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9 (tigervnc): ≥ 0:1.15.0-7.el9_8.2; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions (xorg-x11-server): ≥ 0:1.20.11-21.el9_2; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions (xorg-x11-server-Xwayland): ≥ 0:21.1.3-10.el9_2.1; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions (tigervnc): ≥ 0:1.12.0-14.el9_2.15; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions (xorg-x11-server): ≥ 0:1.20.11-29.el9_4; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions (xorg-x11-server-Xwayland): ≥ 0:22.1.9-8.el9_4.1; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions (tigervnc): ≥ 0:1.13.1-8.el9_4.10; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9.6 Extended Update Support (xorg-x11-server): ≥ 0:1.20.11-34.el9_6; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9.6 Extended Update Support (xorg-x11-server-Xwayland): ≥ 0:23.2.7-6.el9_6.1; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9.6 Extended Update Support (tigervnc): ≥ 0:1.14.1-11.el9_6; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 6 (xorg-x11-server): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 10 (xorg-x11-server-Xwayland): ≥ 0:24.1.9-4.el10_2.2; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 10.0 Extended Update Support (xorg-x11-server-Xwayland): ≥ 0:24.1.5-6.el10_0.1; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 6 Extended Lifecycle Support  - EXTENSION (tigervnc): ≥ 0:1.1.0-25.el6_10.18; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 7 Extended Lifecycle Support (xorg-x11-server): ≥ 0:1.20.4-35.el7_9; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 7 Extended Lifecycle Support (tigervnc): ≥ 0:1.8.0-36.el7_9.5; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 8 (xorg-x11-server-Xwayland): ≥ 0:21.1.3-20.el8_10.2; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 8 (xorg-x11-server): ≥ 0:1.20.11-28.el8_10.2; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 8 (tigervnc): ≥ 0:1.15.0-10.el8_10; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support (xorg-x11-server): ≥ 0:1.20.10-5.el8_4; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support (tigervnc): ≥ 0:1.11.0-8.el8_4.16; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On (xorg-x11-server): ≥ 0:1.20.10-5.el8_4; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On (tigervnc): ≥ 0:1.11.0-8.el8_4.16; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support (xorg-x11-server): ≥ 0:1.20.11-8.el8_6; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support (xorg-x11-server-Xwayland): ≥ 0:21.1.3-2.el8_6.7; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support (tigervnc): ≥ 0:1.12.0-6.el8_6.18; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On (xorg-x11-server): ≥ 0:1.20.11-8.el8_6; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On (xorg-x11-server-Xwayland): ≥ 0:21.1.3-2.el8_6.7; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On (tigervnc): ≥ 0:1.12.0-6.el8_6.18; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 8.8 Telecommunications Update Service (xorg-x11-server): ≥ 0:1.20.11-19.el8_8; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 8.8 Telecommunications Update Service (xorg-x11-server-Xwayland): ≥ 0:21.1.3-13.el8_8.1; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 8.8 Telecommunications Update Service (tigervnc): ≥ 0:1.12.0-15.el8_8.18; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions (xorg-x11-server): ≥ 0:1.20.11-19.el8_8; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions (xorg-x11-server-Xwayland): ≥ 0:21.1.3-13.el8_8.1; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions (tigervnc): ≥ 0:1.12.0-15.el8_8.18; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 9 (xorg-x11-server-Xwayland): ≥ 0:24.1.9-4.el9_8.2; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 9 (xorg-x11-server): ≥ 0:1.20.11-34.el9_8.2; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 9 (tigervnc): ≥ 0:1.15.0-7.el9_8.2; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions (xorg-x11-server): ≥ 0:1.20.11-21.el9_2; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions (xorg-x11-server-Xwayland): ≥ 0:21.1.3-10.el9_2.1; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions (tigervnc): ≥ 0:1.12.0-14.el9_2.15; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions (xorg-x11-server): ≥ 0:1.20.11-29.el9_4; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions (xorg-x11-server-Xwayland): ≥ 0:22.1.9-8.el9_4.1; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions (tigervnc): ≥ 0:1.13.1-8.el9_4.10; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 9.6 Extended Update Support (xorg-x11-server): ≥ 0:1.20.11-34.el9_6; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 9.6 Extended Update Support (xorg-x11-server-Xwayland): ≥ 0:23.2.7-6.el9_6.1; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 9.6 Extended Update Support (tigervnc): ≥ 0:1.14.1-11.el9_6; < * (unaffected, rpm). Source: ADP: redhat-SADP
- Red Hat / Red Hat Enterprise Linux 6 (xorg-x11-server): Version range not reported. Source: ADP: redhat-SADP

## NVD configuration conditions

Affected CPE matches depend on the following AND/OR and negation conditions:

```json
[
  {
    "negate": false,
    "nodes": [
      {
        "cpeMatch": [
          {
            "criteria": "cpe:2.3:a:x.org:x_server:*:*:*:*:*:*:*:*",
            "versionEndExcluding": "21.1.23",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:a:x.org:xwayland:*:*:*:*:*:*:*:*",
            "versionEndExcluding": "24.1.12",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:o:redhat:enterprise_linux:10.0:*:*:*:*:*:*:*",
            "vulnerable": true
          }
        ],
        "negate": false,
        "operator": "OR"
      }
    ],
    "operator": "OR"
  }
]
```

## Severity and prioritization

- CVSS 3.1: 7.8 (high); CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H; source: CNA: redhat

- CVSS 3.1: 7.8 (high); CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H; source: ADP: redhat-SADP

- CVSS 3.1: 7.8 (high); CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H; source: NVD: secalert@redhat.com

- CVSS 3.1: 7.8 (high); CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H; source: NVD: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

- CISA KEV: No listing in collected sources

- EPSS: 0.16% as of 2026-11-04; percentile 4.92%

- SSVC: exploitation none; automatable no; technical impact total; source ADP: CISA-ADP

- Weaknesses: CWE-121

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://access.redhat.com/errata/RHSA-2026:26562 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:26566 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:26590 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:26610 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:26709 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:28923 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:29844 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:36083 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:36085 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:36086 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:36087 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:36632 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:36633 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:36634 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:36768 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:36791 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:36792 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:36798 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:38502 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:38810 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:46377 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:46382 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:46385 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:46392 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:46456 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:46460 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:46473 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:49519 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/security/cve/CVE-2026-50256 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2485380 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

- https://gitlab.freedesktop.org/xorg/xserver/-/commit/bb5158f962dc935e58ef8b4b5fcb31be201a6e07 (CNA: redhat)

- https://lists.x.org/archives/xorg-announce/2026-June/003702.html (CNA: redhat)

- https://redhat.atlassian.net/browse/PSIRTSUPT-16950 (CNA: redhat)

- https://access.redhat.com/security/cve/CVE-2026-50256 (ADP: redhat-SADP; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2485380 (ADP: redhat-SADP; issue-tracking, x_refsource_REDHAT)

- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-50256.json (ADP: redhat-SADP; x_sadp-csaf-vex)

- https://access.redhat.com/errata/RHSA-2026:49519 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:46473 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:36083 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:36798 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:26566 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:28923 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:26709 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:26562 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:46382 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:36792 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:46460 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:36791 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:38810 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:46385 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:36768 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:38502 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:46377 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:36086 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:36633 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:46456 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:36087 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:36632 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:46392 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:36085 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:36634 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:29844 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:26610 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:26590 (ADP: redhat-SADP; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2026:26562 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:26566 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:26590 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:26610 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:26709 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:28923 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:29844 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:36083 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:36085 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:36086 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:36087 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:36632 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:36633 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:36634 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:36768 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:36791 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:36792 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:36798 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:38502 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:38810 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:46377 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:46382 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:46385 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:46392 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:46456 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:46460 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:46473 (secalert@redhat.com)

- https://access.redhat.com/errata/RHSA-2026:49519 (secalert@redhat.com)

- https://access.redhat.com/security/cve/CVE-2026-50256 (secalert@redhat.com; Vendor Advisory)

- https://bugzilla.redhat.com/show_bug.cgi?id=2485380 (secalert@redhat.com; Issue Tracking, Vendor Advisory)

- https://gitlab.freedesktop.org/xorg/xserver/-/commit/bb5158f962dc935e58ef8b4b5fcb31be201a6e07 (secalert@redhat.com; Patch)

- https://lists.x.org/archives/xorg-announce/2026-June/003702.html (secalert@redhat.com; Mailing List, Third Party Advisory)

- https://redhat.atlassian.net/browse/PSIRTSUPT-16950 (secalert@redhat.com; Permissions Required)

- https://access.redhat.com/errata/RHSA-2026:26562 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:26566 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:26590 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:26610 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:26709 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:28923 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:29844 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:36083 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:36085 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:36086 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:36087 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:36632 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:36633 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:36634 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:36768 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:36791 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:36792 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:36798 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:38502 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:38810 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:46377 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:46382 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:46385 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:46392 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:46456 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:46460 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:46473 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/errata/RHSA-2026:49519 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

- https://access.redhat.com/security/cve/CVE-2026-50256 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c; Vendor Advisory)

- https://bugzilla.redhat.com/show_bug.cgi?id=2485380 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c; Issue Tracking, Vendor Advisory)

- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-50256.json (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2026-50256; retrieved 2026-11-04; source updated 2026-11-04

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-50256; retrieved 2026-11-05; source updated 2026-11-04

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-50256; retrieved 2026-11-04; source updated Not reported

Revision: 2cc12085b2cc7d0f8810eda58543dbc0c5a89271fcaedd5497ce7f6a2d98ff7d

Canonical: https://y2.dev/cve/CVE-2026-50256

## Agent and API access

Public CVE pages, Markdown, and JSON are free to read without an account or API key.

- Public catalog: https://y2.dev/cve/index.json. Follow nextCursor with the same search, filters, sort, and limit (1–100). A null cursor marks the end.

- WebMCP: search_cve_disclosures, get_cve_disclosure, get_cve_page_markdown, get_y2_cve_access. Available in compatible browsers.

- Cyber API: https://api.y2.dev/api/v2/cyber/cves and https://api.y2.dev/api/v2/cyber/cves/{cveId}.

- Y2 Pro or Elite: create a workspace API key with the intel:cyber scope and send Authorization: Bearer <Y2_API_KEY>. Setup: https://y2.dev/docs/api/create-key.

- x402: Pay per request without an account or API key. Omit Authorization, read the HTTP 402 PAYMENT-REQUIRED challenge, validate its current requirements, and retry with PAYMENT-SIGNATURE through an authorized payment client. These browser tools never make payments. Guide: https://y2.dev/docs/api/x402.

- OpenAPI: https://y2.dev/api/openapi.yaml. Agent access metadata: https://y2.dev/cve/agent.json.

Collected public records only. Check source status for coverage and freshness.