Debian Security Advisory
DLA-2788-1 strongswan -- LTS security update
- Date Reported:
- 19 Oct 2021
- Affected Packages:
- Security database references:
- In Mitre's CVE dictionary: CVE-2021-41991.
- More information:
Researchers at the United States of America National Security Agency (NSA) identified a denial of services vulnerability in strongSwan, an IKE/IPsec suite.
Once the in-memory certificate cache is full it tries to randomly replace lesser used entries. Depending on the generated random value, this could lead to an integer overflow that results in a double-dereference and a call using out-of-bounds memory that most likely leads to a segmentation fault.
Remote code execution can't be ruled out completely, but attackers have no control over the dereferenced memory, so it seems unlikely at this point.
For Debian 9 stretch, this problem has been fixed in version 5.5.1-4+deb9u5.
We recommend that you upgrade your strongswan packages.
For the detailed security status of strongswan please refer to its security tracker page at: https://security-tracker.debian.org/tracker/strongswan
Further information about Debian LTS security advisories, how to apply these updates to your system and frequently asked questions can be found at: https://wiki.debian.org/LTS