SB2026061605 - Out-of-bounds write in Vim

Description

This security bulletin contains information about 1 vulnerability.

1) Out-of-bounds write (CVE-ID: CVE-2026-55693)

CWE-ID: CWE-787 - Out-of-bounds write

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to out-of-bounds write in the tree_count_words() function in src/spellfile.c when parsing a crafted .spl/.sug spell file pair during spell suggestion loading. A remote attacker can supply a specially crafted spell file pair to cause a denial of service.

User interaction is required: spell checking must be enabled and the user must invoke spell suggestion on a misspelled word.

Remediation

Install update from vendor's website.

References

• https://github.com/vim/vim/security/advisories/GHSA-wgh4-64f7-q3jq
• https://github.com/vim/vim/commit/a80874d9b84a01040e3d1aef2d4a59e1934dafb7