CVE-2021-41991
7.5 HIGHThe in-memory certificate cache in strongSwan before 5.9.4 has a remote integer overflow upon receiving many requests with different cert...
Published: 2021-10-18 · Last updated: 2026-06-17
Severity and scoring
- CVSS
- 7.5 HIGH
- Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- CWE
- CWE-190
Affected products
| Vendor | Product |
|---|---|
| debian | cp_1543-1_firmware, debian_linux, fedora |
| fedoraproject | cp_1543-1_firmware, debian_linux, fedora |
| siemens | cp_1543-1_firmware, debian_linux, fedora |
| strongswan | cp_1543-1_firmware, debian_linux, fedora |
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.
Source: NVD
References
- [NVD]https://nvd.nist.gov/vuln/detail/CVE-2021-41991
- [Patch]https://cert-portal.siemens.com/productcert/pdf/ssa-539476.pdf
- [Other]https://github.com/strongswan/strongswan/releases/tag/5.9.4
- [Other]https://lists.debian.org/debian-lts-announce/2021/10/msg00014.html
- [Other]https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5FJSATD2R2XHTG4P63GCMQ2N7EWKMME5/
- [Other]https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WQSQ3BEC22NF4NCDZVCT4P3Q2ZIAJXGJ/
- [Other]https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Y3TQ32JLJOBJDB2EJKSX2PBPB5NFG2D4/
- [Other]https://www.debian.org/security/2021/dsa-4989
- [Other]https://www.strongswan.org/blog/2021/10/18/strongswan-vulnerability-%28cve-2021-41991%29.html
- [Patch]https://cert-portal.siemens.com/productcert/pdf/ssa-539476.pdf
- [Other]https://github.com/strongswan/strongswan/releases/tag/5.9.4
- [Other]https://lists.debian.org/debian-lts-announce/2021/10/msg00014.html
- [Other]https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5FJSATD2R2XHTG4P63GCMQ2N7EWKMME5/
- [Other]https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WQSQ3BEC22NF4NCDZVCT4P3Q2ZIAJXGJ/
- [Other]https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/Y3TQ32JLJOBJDB2EJKSX2PBPB5NFG2D4/
- [Other]https://www.debian.org/security/2021/dsa-4989
- [Other]https://www.strongswan.org/blog/2021/10/18/strongswan-vulnerability-%28cve-2021-41991%29.html
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