CVE-2026-2903 skvadrik re2c ast.cc check_and_merge_special_rules null pointer dereference
A local attacker can cause a denial of service in re2c via a null pointer dereference in the AST parser.
- 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-2026-2903?
CVE-2026-2903 is a medium-severity vulnerability in skvadrik re2c, published on 22 Feb 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
A flaw has been found in skvadrik re2c up to 4.4. Impacted is the function check_and_merge_special_rules of the file src/parse/ast.cc. This manipulation causes null pointer dereference. The attack can only be executed locally. The exploit has been published and may be used. Patch name: febeb977936f9519a25d9fbd10ff8256358cdb97. It is suggested to install a patch to address this issue.
Which versions are affected by CVE-2026-2903?
How do I fix CVE-2026-2903?
Apply the vendor's patch.
Is CVE-2026-2903 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-2903 exists.
Sources
Also known as AZL-78270, AZL-78273, BELL-CVE-2026-2903, DEBIAN-CVE-2026-2903, ECHO-3d92-841b-34e6, GHSA-7948-p5vf-r2m4 and 1 more.