CVE-2021-27645

Severity: low (CVSS 2.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-02-24 · updated 2026-10-14
Weakness: CWE-415

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.

Affected products

Debian Linux: 10.0
Fedoraproject Fedora: 33, 34
GNU C Library (glibc): from 2.29 through 2.33

References

https://lists.debian.org/debian-lts-announce/2022/10/msg00021.html
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7LZNT6KTMCCWPWXEOGSHD3YLYZKUGMH5/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/I7TS26LIZSOBLGJEZMJX4PXT5BQDE2WS/
https://security.gentoo.org/glsa/202107-07
https://sourceware.org/bugzilla/show_bug.cgi?id=27462
https://lists.debian.org/debian-lts-announce/2022/10/msg00021.html
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7LZNT6KTMCCWPWXEOGSHD3YLYZKUGMH5/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/I7TS26LIZSOBLGJEZMJX4PXT5BQDE2WS/
https://security.gentoo.org/glsa/202107-07
https://sourceware.org/bugzilla/show_bug.cgi?id=27462
https://cert-portal.siemens.com/productcert/html/ssa-398330.html
https://cert-portal.siemens.com/productcert/html/ssa-831302.html

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