CVE-2021-33033 Use after free in n/a
A use-after-free in the Linux kernel CIPSO implementation allows attackers to write arbitrary values, potentially leading to code execution or privilege escalation.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2021-33033?
CVE-2021-33033 is a high-severity use after free vulnerability in Linux kernel, published on 14 May 2021. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
The Linux kernel before 5.11.14 has a use-after-free in cipso_v4_genopt in net/ipv4/cipso_ipv4.c because the CIPSO and CALIPSO refcounting for the DOI definitions is mishandled, aka CID-ad5d07f4a9cd. This leads to writing an arbitrary value.
Weakness: CWE-416
Which versions are affected by CVE-2021-33033?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2021-33033?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2021-33033 being exploited?
There is no known exploitation of CVE-2021-33033 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-6561, DEBIAN-CVE-2021-33033, GHSA-pjv2-crr6-xm2p, UBUNTU-CVE-2021-33033.