NULL pointer dereference in Vim
CVE-2026-32249
Vim is an open source, command line text editor. From 9.1.0011 to before 9.2.0137, Vim's NFA regex compiler, when encountering a collection containing a combining character as the endpoint of a character range (e.g. [0-0\u05bb]), incorrectly emits the composing bytes of that character as separate NFA states. This corrupts the NFA postfix stack, resulting in NFA_START_COLL having a NULL out1 pointer. When nfa_max_width() subsequently traverses the compiled NFA to estimate match width for the look-behind assertion, it dereferences state->out1->out without a NULL check, causing a segmentation fault. This vulnerability is fixed in 9.2.0137.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L.
EPSS exploit prediction
EPSS: 0.002 (7.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 7th percentile — 7.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.001 · newest: 0.002 · change: +0.001
Affected products
- Vim — versions >= 9.1.0011, < 9.2.0137
Weakness classification (CWE)
References
- github.com/vim/vim/security/advisories/GHSA-9phh-423r-778r (Vendor Advisory)
- github.com/vim/vim/commit/36d6e87542cf823d833e451e09a90ee429899cec (Patch)
- github.com/vim/vim/releases/tag/v9.2.0137 (Release Notes)
Frequently asked questions
- What is CVE-2026-32249?
- CVE-2026-32249 is a medium-severity vulnerability in Vim, classified under NULL Pointer Dereference. CVSS score: 5.3/10. Published 2026-03-12.
- How severe is CVE-2026-32249?
- Medium severity. CVSS v3 base score is 5.3 out of 10.