GNU C Library Buffer Overflow Vulnerability
GNU C Library's dynamic loader ld.so contains a buffer overflow vulnerability when processing the GLIBC_TUNABLES environment variable, allowing a local attacker to execute code with elevated privileges.
A local attacker, with a low-privilege account, can achieve full data confidentiality loss, arbitrary modification of data, complete denial of service or system unavailability. Federal agencies are required to remediate by 2023-12-12 under CISA BOD 22-01.
This is a Heap-based Buffer Overflow (CWE-122) vulnerability in 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. Exploitation requires local access, low attack complexity, a low-privilege authenticated account, and no user interaction required.
Probably yes if any of these apply:
Active exploitation documented in the wild. Threat-research write-up: https://www.qualys.com/2023/10/03/cve-2023-4911/looney-tunables-local-privilege-escalation-glibc-ld-so.txt
Manual remediation steps
Apply the Vendor Patch
This vulnerability is in the CISA Known Exploited Vulnerabilities catalog — apply the vendor's security update as soon as possible.
CISA required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
References
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References