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UK Cyber Defence
VulnerabilityAnalyzed

CVE-2023-4911

GNU C Library Buffer Overflow Vulnerability

KEVHIGH 7.8EPSS 81.4%

Does this matter?

Known to be exploited in the wild (CISA KEV, CISA remediation deadline 12 December 2023). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.

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.

CVSS 3.1
7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS
81.42% probability · 100th percentile
CISA KEV
Listed 21 November 2023 · due 12 December 2023
Weakness
CWE-122, CWE-787
Affected
netapp/bootstrap os · siemens/simatic s7-1500 cpu 1518-4 pn\/dp mfp firmware · siemens/simatic s7-1500 cpu 1518f-4 pn\/dp mfp firmware · siemens/siplus s7-1500 cpu 1518-4 pn\/dp mfp firmware · siemens/simatic s7-1500 tm mfp firmware · gnu/glibc · fedoraproject/fedora · redhat/codeready linux builder · redhat/codeready linux builder eus · redhat/codeready linux builder for arm64 · redhat/codeready linux builder for arm64 eus · redhat/codeready linux builder for ibm z systems · redhat/codeready linux builder for ibm z systems eus · redhat/codeready linux builder for power little endian · redhat/codeready linux builder for power little endian eus · redhat/virtualization · redhat/virtualization host · redhat/enterprise linux · redhat/enterprise linux eus · redhat/enterprise linux for arm 64 · +19 more
Source
secalert@redhat.com

CISA notes

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable. This vulnerability affects a common open-source component, third-party library, or a protocol used by different products. Please check with specific vendors for information on patching status. For more information, please see: https://sourceware.org/git/?p=glibc.git;a=commitdiff;h=1056e5b4c3f2d90ed2b4a55f96add28da2f4c8fa, https://access.redhat.com/security/cve/cve-2023-4911, https://www.debian.org/security/2023/dsa-5514 ; https://nvd.nist.gov/vuln/detail/CVE-2023-4911

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.