Buffer overflow in Neovim

CVE-2026-45130

Vim is an open source, command line text editor. Prior to version 9.2.0450, a heap buffer overflow exists in read_compound() in src/spellfile.c when loading a crafted spell file (.spl) with UTF-8 encoding active. An attacker-controlled length field in the spell file's compound section overflows a 32-bit signed integer multiplication, causing a small buffer to be allocated for a write loop that runs many iterations, overflowing the heap. Because the 'spelllang' option can be set from a modeline, a text file modeline can trigger spell file loading if a malicious .spl file has been planted on the runtimepath. This issue has been patched in version 9.2.0450.

Vulnerability class: Buffer Overflow

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.6 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H.

EPSS exploit prediction

EPSS: 0.002 (8.4th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 8th percentile — 8.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-45130: held from 0.002 to 0.002.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: -0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-45130?
CVE-2026-45130 is a medium-severity vulnerability in Neovim, classified under Heap-based Buffer Overflow. CVSS score: 6.6/10. Published 2026-05-08.
How severe is CVE-2026-45130?
Medium severity. CVSS v3 base score is 6.6 out of 10.