CVE-2021-3999
A flaw was found in glibc. An off-by-one buffer overflow and underflow in getcwd() may lead to memory corruption when the size of the buffer is exactly 1. A local attacker who can control the input
02 Description
A flaw was found in glibc. An off-by-one buffer overflow and underflow in getcwd() may lead to memory corruption when the size of the buffer is exactly 1. A local attacker who can control the input
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 ImpacttotalSuccessful exploitation gives total control of the vulnerable component.
- EPSS probability
- 0.80% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 56.6% of scored records. A rank, not a probability.
- NVD base score
- 7.8 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- NVD analysis status
- Modified. NVD last modified this record on 2026-10-14.
- Red Hat severity
- Moderate. 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
- 2022-08-24 00:00Z4 YR AGO
- Last updated
- 2026-10-14 09:59Z15 DAYS AGO
- Reserved
- 2021-11-22
- Assigning CNA
- redhat
- Record state
- PUBLISHED
- Severity
- High (CVSS 7.8)
- CNA CVSS vector
- CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- Weaknesses
- CWE-193Off-by-one ErrorBase
- Data version
- 5.2
- Document digest
- c7585c5fca18bc894b3efd6cc3ad4cc26744e3245a6ddaa5d82f2fd48297fdc1
05 Affected products
06 References
- www.openwall.comhttps://www.openwall.com/lists/oss-security/2022/01/24/4
- sourceware.orghttps://sourceware.org/bugzilla/show_bug.cgi?id=28769
- sourceware.orghttps://sourceware.org/git/gitweb.cgi?p=glibc.git%3Bh=23e0e8f5f1fb5ed150253d986ecccdc90c2dcd5e
- bugzilla.redhat.comhttps://bugzilla.redhat.com/show_bug.cgi?id=2024637
- access.redhat.comhttps://access.redhat.com/security/cve/CVE-2021-3999
- security-tracker.debian.orghttps://security-tracker.debian.org/tracker/CVE-2021-3999
- lists.debian.org[debian-lts-announce] 20221017 [SECURITY] [DLA 3152-1] glibc security updatehttps://lists.debian.org/debian-lts-announce/2022/10/msg00021.html
- security.netapp.comhttps://security.netapp.com/advisory/ntap-20221104-0001/
- 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_5.3
- glibc-benchtests Fixed in 2.28-164.el8_5.3
- glibc-nss-devel Fixed in 2.28-164.el8_5.3
- glibc-static Fixed in 2.28-164.el8_5.3
- glibc-utils Fixed in 2.28-164.el8_5.3
- nss_hesiod Fixed in 2.28-164.el8_5.3
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_5.3
- glibc-benchtests Fixed in 2.28-164.el8_5.3
- glibc-nss-devel Fixed in 2.28-164.el8_5.3
- glibc-static Fixed in 2.28-164.el8_5.3
- glibc-utils Fixed in 2.28-164.el8_5.3
- nss_hesiod Fixed in 2.28-164.el8_5.3
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 2.33-4
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 13
- glibc Fixed in 2.33-4
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Debian 14
- glibc Fixed in 2.33-4
Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu 18.04 LTS
- glibc Fixed in 2.27-3ubuntu1.5
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. 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.
Ubuntu Pro 14.04 LTS
- eglibc Fixed in 2.19-0ubuntu6.15+esm3Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro 16.04 LTS
- glibc Fixed in 2.23-0ubuntu11.3+esm1Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro
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.