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.

References

• https://nvd.nist.gov/vuln/detail/CVE-2026-2903
• skvadrik/re2c#571
• skvadrik/re2c#571 (comment)
• skvadrik/re2c@febeb97
• https://github.com/oneafter/0202/blob/main/re/repro
• https://github.com/skvadrik/re2c
• https://vuldb.com/?ctiid.347210
• https://vuldb.com/?id.347210
• https://vuldb.com/?submit.755030