How severe is CVE-2023-4911?

CVE-2023-4911 has a CVSS score of 7.8/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2023-4911?

Affected package information for CVE-2023-4911 is not yet fully mapped. Check the official advisory links for details.

How do I fix CVE-2023-4911?

No fixed version has been published for CVE-2023-4911 yet. Monitor the advisory for updates, apply mitigations recommended by the vendor, and use O3 Security to track when a fix becomes available in your stack.

Is CVE-2023-4911 actively exploited in the wild?

Yes. There are 28 known exploit references for CVE-2023-4911, including 1 documented proof-of-concept exploit on Exploit-DB and 18 in-the-wild exploitations observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2023-4911?

CVE-2023-4911 has an EPSS (Exploit Prediction Scoring System) score of 65.0%, placing it in the 98th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. A score above 50% indicates significantly elevated exploitation risk — immediate patching is strongly recommended.

Is CVE-2023-4911 in the CISA Known Exploited Vulnerabilities catalog?

Yes. CVE-2023-4911 (GNU C Library Buffer Overflow Vulnerability) was added to CISA's Known Exploited Vulnerabilities (KEV) catalog on 2023-11-21. CISA required all US federal civilian agencies to remediate this vulnerability by 2023-12-12. The required action was: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable. Being listed in the KEV catalog is the strongest possible confirmation of active exploitation — treat this as a critical priority.

When was CVE-2023-4911 published, and has it been updated?

CVE-2023-4911 was published on October 3, 2023 and was last updated on April 16, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

CISA KEV·Added 2023-11-21 — agencies required to remediate by 2023-12-12

CVE-2023-4911

HIGH

Published

Oct 3, 2023

Updated

Apr 16, 2026

Affected

0 pkgs

Patched

None yet

Exploits

28 known

EPSS Exploitation Probability

via FIRST.org ↗

65.0%probability of exploitation in next 30 days

High Risk98th percentile+0.71%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Description

A buffer overflow was discovered in the GNU C Library's dynamic loader ld.so while processing the GLIBC_TUNABLES environment variable. This issue could allow a local attacker to use maliciously crafted GLIBC_TUNABLES environment variables when launching binaries with SUID permission to execute code with elevated privileges.

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

EDB-52479locallinux

glibc 2.38 - Buffer Overflow

by Beatriz Fresno Naumova · Feb 11, 2026

Exploit-DB Source

Frequently Asked Questions

O3 Security · Impact-Aware SCA

Is CVE-2023-4911 in your stack?

O3 detects CVE-2023-4911 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

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