An issue was discovered in Matrix libolm through 3.2.16. Cache-timing attacks can occur due to use of base64 when decoding group session keys. This refers to the libolm implementation of Olm. NOTE: This vulnerability only affects products that are no longer supported by the maintainer.
Severity
CVSS 3.1
5.3 medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
EPSS
0.5% chance of exploitation in the next 30 days; higher than 45% of CVEs (scores of 2026-10-31)