CVE-2021-27645
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
02 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
03 Exploitation and scoring
- Exploitation
- Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.
- SSVC decision
- ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
- AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
- Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.
- EPSS probability
- 0.38% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 32.3% of scored records. A rank, not a probability.
- NVD base score
- 2.5 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L
- NVD analysis status
- Modified. NVD last modified this record on 2026-10-14.
- Red Hat severity
- Low. Red Hat's rating for its own products, not a CVSS rating.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2021-02-24 00:00Z5 YR AGO
- Last updated
- 2026-10-14 11:39Z15 DAYS AGO
- Reserved
- 2021-02-24
- Assigning CNA
- mitre
- Record state
- PUBLISHED
- Severity
- Low (CVSS 2.5)
- CNA CVSS vector
- CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L
- Weaknesses
- CWE-415Double FreeVariant
- Data version
- 5.2
- Document digest
- 60b4c99fca6a567edc4a120fc0fb1fa89fe809dbfc1ff077e960f26db27ea4d2
05 Affected products
06 References
- sourceware.orghttps://sourceware.org/bugzilla/show_bug.cgi?id=27462
- lists.fedoraproject.orgFEDORA-2021-6749bfcfd9https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/I7TS26LIZSOBLGJEZMJX4PXT5BQDE2WS/
- lists.fedoraproject.orgFEDORA-2021-2ba993d6c5https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7LZNT6KTMCCWPWXEOGSHD3YLYZKUGMH5/
- security.gentoo.orgGLSA-202107-07https://security.gentoo.org/glsa/202107-07
- lists.debian.org[debian-lts-announce] 20221017 [SECURITY] [DLA 3152-1] glibc security updatehttps://lists.debian.org/debian-lts-announce/2022/10/msg00021.html
- cert-portal.siemens.comhttps://cert-portal.siemens.com/productcert/html/ssa-831302.html
- cert-portal.siemens.comhttps://cert-portal.siemens.com/productcert/html/ssa-398330.html
07 Fixed in
AlmaLinux 8
- compat-libpthread-nonshared Fixed in 2.28-164.el8
- glibc-benchtests Fixed in 2.28-164.el8
- glibc-nss-devel Fixed in 2.28-164.el8
- glibc-static Fixed in 2.28-164.el8
- glibc-utils Fixed in 2.28-164.el8
- nss_hesiod Fixed in 2.28-164.el8
Source: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.
Arch Linux
- glibc Fixed in 2.34-1
Source: Arch Linux Security Tracker, the Arch Linux security team. Reformatted by exploit.cc.
CloudLinux 8
- compat-libpthread-nonshared Fixed in 2.28-164.el8
- glibc-benchtests Fixed in 2.28-164.el8
- glibc-nss-devel Fixed in 2.28-164.el8
- glibc-static Fixed in 2.28-164.el8
- glibc-utils Fixed in 2.28-164.el8
- nss_hesiod Fixed in 2.28-164.el8
Derived from AlmaLinux 8. Partial coverage: only packages taken from AlmaLinux 8 are listed.
Source: CloudLinux errata, CloudLinux Inc. Derived from: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.
Debian 12
- glibc Fixed in 2.31-10
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 13
- glibc Fixed in 2.31-10
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 14
- glibc Fixed in 2.31-10
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 20.04 LTS
- glibc Fixed in 2.31-0ubuntu9.7
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
A release or ecosystem missing from this list has no record here. It may be unaffected or not covered by the source. Source notices and licences.