CVE-2021-34813 Memory corruption in n/a
A malicious Matrix homeserver can crash clients via a stack-based buffer overflow in libolm, potentially enabling remote code execution in nonstandard builds.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2021-34813?
CVE-2021-34813 is a critical memory corruption vulnerability in n/a, published on 16 Jun 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-787
Which versions are affected by CVE-2021-34813?
It affects 1 product.
Products include Matrix Olm.
How do I fix CVE-2021-34813?
Upgrade to a fixed version.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2021-34813 being exploited?
There is no known exploitation of CVE-2021-34813 in the wild and no public exploit code.
Other vulnerabilities in n/a
Sources
Also known as DEBIAN-CVE-2021-34813, GHSA-269w-9hm6-g22q, UBUNTU-CVE-2021-34813, USN-5194-1.