CVE-2021-3998
A flaw was found in glibc. The realpath() function can mistakenly return an unexpected value,...
A flaw was found in glibc. The realpath() function can mistakenly return an unexpected value, potentially leading to information leakage and disclosure of sensitive data.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
A flaw was found in glibc. The realpath() function can mistakenly return an unexpected value, potentially leading to information leakage and disclosure of sensitive data.
- Record
CVE-2021-3998- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-125, CWE-252
- Updated
- 2026-11-02
CVE List
A flaw was found in glibc. The realpath() function can mistakenly return an unexpected value, potentially leading to information leakage and disclosure of sensitive data.
- Record
CVE-2021-3998- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-125
- Updated
- 2026-11-02
EUVDEUVD-2021-27188
A flaw was found in glibc. The realpath() function can mistakenly return an unexpected value, potentially leading to information leakage and disclosure of sensitive data.
- Record
EUVD-2021-27188- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-32pr-wg5j-9rwr
A flaw was found in glibc. The realpath() function can mistakenly return an unexpected value,...
A flaw was found in glibc. The realpath() function can mistakenly return an unexpected value, potentially leading to information leakage and disclosure of sensitive data.
- Record
GHSA-32pr-wg5j-9rwr- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-125, CWE-252
- Updated
- 2026-11-02
OSVAZL-10675
CVE-2021-3998 affecting package glibc for versions less than 2.35-7
A flaw was found in glibc. The realpath() function can mistakenly return an unexpected value, potentially leading to information leakage and disclosure of sensitive data.
- Record
AZL-10675- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
OSV
A flaw was found in glibc. The realpath() function can mistakenly return an unexpected value, potentially leading to information leakage and disclosure of sensitive data.
- Record
CVE-2021-3998- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
Show 4 moreShow less
OSVDEBIAN-CVE-2021-3998
A flaw was found in glibc. The realpath() function can mistakenly return an unexpected value, potentially leading to information leakage and disclosure of sensitive data.
- Record
DEBIAN-CVE-2021-3998- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
OSVUBUNTU-CVE-2021-3998
A flaw was found in glibc. The realpath() function can mistakenly return an unexpected value, potentially leading to information leakage and disclosure of sensitive data.
- Record
UBUNTU-CVE-2021-3998- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
OSVopenSUSE-SU-2024:11850-1 No score
glibc-2.35-1.1 on GA media
These are all security issues fixed in the glibc-2.35-1.1 package on the GA media of openSUSE Tumbleweed.
- Record
openSUSE-SU-2024:11850-1- Updated
- 2026-11-02
OSVUSN-5310-1 No score
glibc vulnerabilities
Jan Engelhardt, Tavis Ormandy, and others discovered that the GNU C Library iconv feature incorrectly handled certain input sequences. An attacker could possibly use this issue to cause the GNU C Library to hang or crash, resulting in a denial of service. This issue only affected Ubuntu 18.04 LTS and Ubuntu 20.04 LTS. (CVE-2016-10228, CVE-2019-25013, CVE-2020-27618, CVE-2020-29562, CVE-2021-3326)
Jason Royes and Samuel Dytrych discovered that the GNU C Library incorrectly handled signed comparisons on ARMv7 targets. A remote attacker could use this issue to cause the GNU C Library to crash, resulting in a denial of service, or possibly execute arbitrary code. This issue only affected Ubuntu 18.04 LTS and Ubuntu 20.04 LTS. (CVE-2020-6096)
It was discovered that the GNU C Library nscd daemon incorrectly handled certain netgroup lookups. An attacker could possibly use this issue to cause the GNU C Library to crash, resulting in a denial of service. This issue only affected Ubuntu 20.04 LTS. (CVE-2021-27645)
It was discovered that the GNU C Library wordexp function incorrectly handled certain patterns. An attacker could use this issue to cause the GNU C Library to crash, resulting in a denial of service, or possibly obtain sensitive information. This issue only affected Ubuntu 18.04 LTS and Ubuntu 20.04 LTS. (CVE-2021-35942)
It was discovered that the GNU C Library realpath function incorrectly handled return values. An attacker could possibly use this issue to obtain sensitive information. This issue only affected Ubuntu 21.10. (CVE-2021-3998)
It was discovered that the GNU C library getcwd function incorrectly handled buffers. An attacker could use this issue to cause the GNU C Library to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2021-3999)
It was discovered that the GNU C Library sunrpc module incorrectly handled buffer lengths. An attacker could possibly use this issue to cause the GNU C Library to crash, resulting in a denial of service. (CVE-2022-23218, CVE-2022-23219)
- Record
USN-5310-1- Updated
- 2026-11-02
Affected products
- gnu glibc
- the gnu c library glibc
- netapp h300s firmware
- netapp h410c firmware
- netapp h410s firmware
- netapp h500s firmware
- netapp h700s firmware
- netapp ontap select deploy administration utility
- siemens simatic s7-1500 cpu 1518-4 pn/dp mfp
- siemens simatic s7-1500 cpu 1518f-4 pn/dp mfp
- siemens siplus s7-1500 cpu 1518-4 pn/dp mfp
Affected packages
| Package | Affected | Fixed |
|---|---|---|
glibcAzure Linux:2 |
before 2.35-7 | 2.35-7 |
glibcDebian:12 |
before 2.33-4 | 2.33-4 |
glibcDebian:13 |
before 2.33-4 | 2.33-4 |
glibcDebian:14 |
before 2.33-4 | 2.33-4 |
glibcUbuntu:18.04:LTS From an advisory covering 12 CVEs |
before 2.27-3ubuntu1.5, plus listed versions 2.26-0ubuntu22.26-0ubuntu2.12.27-0ubuntu22.27-0ubuntu32.27-3ubuntu12.27-3ubuntu1.22.27-3ubuntu1.32.27-3ubuntu1.4 |
2.27-3ubuntu1.5 |
glibcUbuntu:20.04:LTS From an advisory covering 12 CVEs |
before 2.31-0ubuntu9.7, plus listed versions 2.30-0ubuntu22.30-0ubuntu32.31-0ubuntu52.31-0ubuntu62.31-0ubuntu7 Show 4 moreShow less2.31-0ubuntu92.31-0ubuntu9.12.31-0ubuntu9.22.31-0ubuntu9.3 |
2.31-0ubuntu9.7 |
glibcopenSUSE:Tumbleweed From an advisory covering 4 CVEs |
before 2.35-1.1 | 2.35-1.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| affected | ||
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-3998 is a high vulnerability (CVSS 7.5) in Gnu Glibc, published February 1, 2022. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 2.20%, the 82nd percentile. Fixed in glibc 2.35-7.
References
openwall.com/lists/oss-security/2022/01/24/4
sourceware.org/bugzilla/show_bug.cgi?id=28770
bugzilla.redhat.com/show_bug.cgi?id=2024633
access.redhat.com/security/cve/CVE-2021-3998
Show 26 moreShow less
security-tracker.debian.org/tracker/CVE-2021-3998
security.netapp.com/advisory/ntap-20221020-0003
cert-portal.siemens.com/productcert/html/ssa-831302.html
nvd.nist.gov/vuln/detail/CVE-2021-3998
github.com/advisories/GHSA-32pr-wg5j-9rwr
ubuntu.com/security/CVE-2021-3998
cve.org/CVERecord?id=CVE-2021-3998
suse.com/security/cve/CVE-2021-3998