{"cve":"CVE-2023-3138","nvd":{"published":"2023-06-28T21:15:10.247","modified":"2026-06-17T06:13:26.193","status":"Modified","description":"A vulnerability was found in libX11. The security flaw occurs because the functions in src/InitExt.c in libX11 do not check that the values provided for the Request, Event, or Error IDs are within the bounds of the arrays that those functions write to, using those IDs as array indexes. They trust that they were called with values provided by an Xserver adhering to the bounds specified in the X11 protocol, as all X servers provided by X.Org do. As the protocol only specifies a single byte for these values, an out-of-bounds value provided by a malicious server (or a malicious proxy-in-the-middle) can only overwrite other portions of the Display structure and not write outside the bounds of the Display structure itself, possibly causing the client to crash with this memory corruption.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-787","CWE-119"],"references":["https://access.redhat.com/security/cve/CVE-2023-3138","https://gitlab.freedesktop.org/xorg/lib/libx11/-/commit/304a654a0d57bf0f00d8998185f0360332cfa36c","https://lists.x.org/archives/xorg-announce/2023-June/003406.html","https://lists.x.org/archives/xorg-announce/2023-June/003407.html","https://security.netapp.com/advisory/ntap-20231208-0008/"],"products":["redhat:enterprise_linux","x.org:libx11"],"source":"nvd","synced_at":"2026-10-19T21:38:30.124994567+00:00"},"epss":{"cve":"CVE-2023-3138","score":0.01656,"percentile":0.76607,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}