# CVE-2023-43787: Libx11: integer overflow in xcreateimage() leading to a heap overflow

Status: published. Published: 2023-10-10. Updated: 2026-11-07.

A vulnerability was found in libX11 due to an integer overflow within the XCreateImage() function. This flaw allows a local user to trigger an integer overflow and execute arbitrary code with elevated privileges.

## Remediation

No remediation reported in collected sources

## Affected products and versions

-  /  (libX11): ≥ 0; < 1.8.7 (affected, semver). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 8 (libX11): ≥ 0:1.6.8-8.el8; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 9 (libX11): ≥ 0:1.7.0-9.el9; < * (unaffected, rpm). Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 6 (libX11): Version range not reported. Source: CNA: redhat
- Red Hat / Red Hat Enterprise Linux 7 (libX11): Version range not reported. Source: CNA: redhat

## Severity and prioritization

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

- CISA KEV: No listing in collected sources

- EPSS: 0.47% as of 2026-11-06; percentile 41.23%

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

- Weaknesses: CWE-122

## Exploit evidence

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

## References

- https://access.redhat.com/errata/RHSA-2024:2145 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/errata/RHSA-2024:2973 (CNA: redhat; vendor-advisory, x_refsource_REDHAT)

- https://access.redhat.com/security/cve/CVE-2023-43787 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2242254 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

- http://www.openwall.com/lists/oss-security/2024/01/24/9 (ADP: CVE; x_transferred)

- https://access.redhat.com/errata/RHSA-2024:2145 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/errata/RHSA-2024:2973 (ADP: CVE; vendor-advisory, x_refsource_REDHAT, x_transferred)

- https://access.redhat.com/security/cve/CVE-2023-43787 (ADP: CVE; vdb-entry, x_refsource_REDHAT, x_transferred)

- https://bugzilla.redhat.com/show_bug.cgi?id=2242254 (ADP: CVE; issue-tracking, x_refsource_REDHAT, x_transferred)

- https://jfrog.com/blog/xorg-libx11-vulns-cve-2023-43786-cve-2023-43787-part-two/ (ADP: CVE; x_transferred)

- https://security.netapp.com/advisory/ntap-20231103-0006/ (ADP: CVE; x_transferred)

- https://lists.debian.org/debian-lts-announce/2023/10/msg00005.html (ADP: CVE)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2023-43787; retrieved 2026-11-07; source updated 2026-11-07

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2023-43787; retrieved 2026-11-07; source updated Not reported

Revision: 745595e4919ac2439641017ecea5f1f6554719132d8c9843e85547f5cf04470c

Canonical: https://y2.dev/cve/CVE-2023-43787

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