CVE-2021-34813
9.8
CRITICAL
CVSS 3.1
EPSS 4.5%
Description
Matrix libolm before 3.2.3 allows a malicious Matrix homeserver to crash a client (while it is attempting to retrieve an Olm encrypted room key backup from the homeserver) because olm_pk_decrypt has a stack-based buffer overflow. Remote code execution might be possible for some nonstandard build configurations.
How to fix CVE-2021-34813
No fixed version has been published yet. Mitigate by removing the affected package or applying upstream guidance from the references below.
- Debian/olm—no fix listed
Is CVE-2021-34813 being exploited?
Low — EPSS is 4.5%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | CRITICAL9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |