Critical severity · published Apr 30, 2021
CVE-2021-31873
An issue was discovered in klibc before 2.0.9
9.8
CVSS
2.2%
EPSS
No
On KEV
Description
An issue was discovered in klibc before 2.0.9. Additions in the malloc() function may result in an integer overflow and a subsequent heap buffer overflow.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.2% · higher than 82% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
9.0 · source: NVD
KL
Klibc · Klibc Project
before 2.0.9 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-31873
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-31873
Mailing List
http://www.openwall.com/lists/oss-security/2021/04/30/1
Patch
https://git.kernel.org/pub/scm/libs/klibc/klibc.git/commit/?id=a31ae8c508fc8d1bca4f57e9f9f88127572d5202
github.com
https://github.com/huolinjue/klibc/commit/a31ae8c508fc8d1bca4f57e9f9f88127572d5202
Release Notes
https://kernel.org/pub/linux/libs/klibc/2.0/
Mailing List
https://lists.debian.org/debian-lts-announce/2021/06/msg00025.html
Mailing List
https://lists.zytor.com/archives/klibc/2021-April/004593.html
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