CVE-2021-41991

HIGH

strongSwan 4.2.10-5.9.3 - Remote Integer Overflow in Certificate Cache

Title source: llm

Description

The in-memory certificate cache in strongSwan before 5.9.4 has a remote integer overflow upon receiving many requests with different certificates to fill the cache and later trigger the replacement of cache entries. The code attempts to select a less-often-used cache entry by means of a random number generator, but this is not done correctly. Remote code execution might be a slight possibility.

References (8)

Core 8

Core References

Third Party Advisory x_refsource_misc

https://github.com/strongswan/strongswan/releases/tag/5.9.4

Various Sources x_refsource_confirm

https://www.strongswan.org/blog/2021/10/18/strongswan-vulnerability-%28cve-2021-41991%29.html

Third Party Advisory vendor-advisory x_refsource_debian

https://www.debian.org/security/2021/dsa-4989

Mailing List, Third Party Advisory mailing-list x_refsource_mlist

https://lists.debian.org/debian-lts-announce/2021/10/msg00014.html

Mailing List, Third Party Advisory vendor-advisory x_refsource_fedora

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5FJSATD2R2XHTG4P63GCMQ2N7EWKMME5/

Mailing List, Third Party Advisory vendor-advisory x_refsource_fedora

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WQSQ3BEC22NF4NCDZVCT4P3Q2ZIAJXGJ/

Mailing List, Third Party Advisory vendor-advisory x_refsource_fedora

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Y3TQ32JLJOBJDB2EJKSX2PBPB5NFG2D4/

Patch, Third Party Advisory x_refsource_confirm

https://cert-portal.siemens.com/productcert/pdf/ssa-539476.pdf

Scores

CVSS v3 7.5

EPSS 0.0219

EPSS Percentile 84.6%

Attack Vector NETWORK

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Details

CWE

CWE-190

Status published

Products (29)

debian/debian_linux 9.0

debian/debian_linux 10.0

debian/debian_linux 11.0

fedoraproject/fedora 33

fedoraproject/fedora 34

fedoraproject/fedora 35

siemens/cp_1543-1_firmware

siemens/scalance_sc622-2c_firmware

siemens/scalance_sc632-2c_firmware

siemens/scalance_sc636-2c_firmware

... and 19 more

Published Oct 18, 2021

Tracked Since Feb 18, 2026