CVE-2021-34550 Memory corruption in n/a

High 7.5 Published 29 Jun 2021 Updated 4 Aug 2024

A crafted onion service descriptor causes out-of-bounds memory access and client crashes in Tor, requiring an upgrade to mitigate.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2021-34550?

CVE-2021-34550 is a high-severity memory corruption vulnerability in n/a, published on 29 Jun 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

An issue was discovered in Tor before 0.4.6.5, aka TROVE-2021-006. The v3 onion service descriptor parsing allows out-of-bounds memory access, and a client crash, via a crafted onion service descriptor

Weakness: CWE-119

Which versions are affected by CVE-2021-34550?

It affects 1 product.

Products include Torproject Tor.

How do I fix CVE-2021-34550?

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-2021-34550 being exploited?

There is no known exploitation of CVE-2021-34550 in the wild and no public exploit code.

Sources

Also known as DEBIAN-CVE-2021-34550, GHSA-28mq-w7hj-99g5, UBUNTU-CVE-2021-34550.