CVE-2021-4008

Status: ModifiedHigh (7.8)—
A flaw was found in xorg-x11-server in versions before 21.1.2 and before 1.20.14. An out-of-bounds access can occur in the SProcRenderCompositeGlyphs function. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
CVSS

Version: 3.1
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Base score: 7.8
Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.56%
Percentile among all scored CVEs: 45
Score date: 10/7/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (3)

Debian — Debian Linux Fedoraproject — Fedora X.org — X Server
CWEs

CWE-119
CWE-119
References

Raw JSON (NVD)

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