CISA KEV · Known exploitedHigh

CVE-2023-4911

GNU GNU C Library

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.

CVSS
7.8
EPSS
81.4%
99.6% percentile
CISA KEV
Listed
Published
2023.10.04
PRIORITY ASSESSMENT

Immediate review

CISA has listed this vulnerability in the Known Exploited Vulnerabilities catalog.

Known exploitationConfirmed by CISA KEV
Exploit probability81.4%
Technical severityCVSS 7.8

Vulnerability overview

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.

Affected product and versions

Product
GNU GNU C Library
Affected versions
2.34, V3.1.5, >= 3.1.5, < 1.1, >= 2.34 < 2.39, 37, 38, 39, 9.0, 8.6, 9.2, 9.4, 9.6, 9.0 aarch64, 9.2 aarch64, 9.4 aarch64, 9.6 aarch64, 9.0 s390x, 9.2 s390x, 9.4 s390x
Fixed versions
1.1, 2.39

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
CISA required action

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

Due date: 2023.12.12
  1. 1
    Identify

    Confirm that GNU GNU C Library and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE
CWE-122, CWE-787
KEV added
2023.11.21
Ransomware use
미확인
CVE-2023-4911 — GNU GNU C Library | SECUFOCUS NOW