# CVE-2023-43785: Libx11: out-of-bounds memory access in _xkbreadkeysyms()

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

A vulnerability was found in libX11 due to a boundary condition within the _XkbReadKeySyms() function. This flaw allows a local user to trigger an out-of-bounds read error and read the contents of memory on the system.

## 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: 6.5 (medium); CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N; source: CNA: redhat

- CISA KEV: No listing in collected sources

- EPSS: 0.67% as of 2026-11-06; percentile 52.13%

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

- Weaknesses: CWE-787

## 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-2023-43785 (CNA: redhat; vdb-entry, x_refsource_REDHAT)

- https://bugzilla.redhat.com/show_bug.cgi?id=2242252 (CNA: redhat; issue-tracking, x_refsource_REDHAT)

- 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-2023-43785 (ADP: CVE; vdb-entry, x_refsource_REDHAT, x_transferred)

- https://bugzilla.redhat.com/show_bug.cgi?id=2242252 (ADP: CVE; issue-tracking, x_refsource_REDHAT, x_transferred)

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

- https://lists.debian.org/debian-lts-announce/2023/10/msg00004.html (ADP: CVE)

## Provenance

- CNA: redhat: https://www.cve.org/CVERecord?id=CVE-2023-43785; retrieved 2026-11-07; source updated 2026-11-07

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2023-43785; retrieved 2026-11-07; source updated Not reported

Revision: a5f6f1afa943967dd3c5566fd105a030df32f47eebb977add393f422d9b3dc7a

Canonical: https://y2.dev/cve/CVE-2023-43785

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