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

• https://nvd.nist.gov/vuln/detail/CVE-2021-27645
• https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/7LZNT6KTMCCWPWXEOGSHD3YLYZKUGMH5/
• https://lists.fedoraproject.org/archives/list/package-announce@lists.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