CVE-2021-27645

LOW

GNU C Library <2.34 - Use After Free

Title source: llm

Description

The nameserver caching daemon (nscd) in the GNU C Library (aka glibc or libc6) 2.29 through 2.33, when processing a request for netgroup lookup, may crash due to a double-free, potentially resulting in degraded service or Denial of Service on the local system. This is related to netgroupcache.c.

References (5)

[Mailing List, Third Party Advisory] https://lists.debian.org/debian-lts-announce/2022/10/msg00021.html

[Third Party Advisory] https://security.gentoo.org/glsa/202107-07

[Issue Tracking, Patch, Third Party Advisory] https://sourceware.org/bugzilla/show_bug.cgi?id=27462

[Mailing List, Third Party Advisory] https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7LZNT6KTMCCWPWXEOGSHD3YLYZKUGMH5/

[Mailing List, Third Party Advisory] https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/I7TS26LIZSOBLGJEZMJX4PXT5BQDE2WS/

Scores

CVSS v3 2.5

EPSS 0.0004

EPSS Percentile 10.9%

Attack Vector LOCAL

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L

Classification

CWE

CWE-415

Status published

Affected Products (4)

gnu/glibc < 2.33

fedoraproject/fedora

fedoraproject/fedora

debian/debian_linux

Timeline

Published Feb 24, 2021

Tracked Since Feb 18, 2026