CVE-2021-44538 Memory corruption in n/a
A buffer overflow in libolm allows remote attackers to potentially execute code or cause denial of service via crafted messages.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2021-44538?
CVE-2021-44538 is a critical memory corruption vulnerability in Debian Debian Linux, published on 14 Dec 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
The olm_session_describe function in Matrix libolm before 3.2.7 is vulnerable to a buffer overflow. The Olm session object represents a cryptographic channel between two parties. Therefore, its state is partially controllable by the remote party of the channel. Attackers can construct a crafted sequence of messages to manipulate the state of the receiver's session in such a way that, for some buffer sizes, a buffer overflow happens on a call to olm_session_describe. Furthermore, safe buffer sizes were undocumented. The overflow content is partially controllable by the attacker and limited to ASCII spaces and digits. The known affected products are Element Web And SchildiChat Web.
Weakness: CWE-119
Which versions are affected by CVE-2021-44538?
It affects 6 products.
Products include Cinny Project Cinny, Debian Debian Linux, Matrix Element, Matrix Javascript Sdk, Matrix Olm, Schildi Schildichat.
How do I fix CVE-2021-44538?
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-2021-44538 being exploited?
There is no known exploitation of CVE-2021-44538 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2021-44538, GHSA-q7f4-j236-f4hc, MGASA-2021-0571, UBUNTU-CVE-2021-44538.