CVE-2026-57455: Vim: Stack out-of-bounds write in `spell_soundfold_sofo()` via an over-length `soundfold()` argument
Last updated 2 July 2026
Other sources
Vim is an open source, command line text editor. Prior to 9.2.0698, the single-byte branch of spellsoundfoldsofo() in src/spell.c translates a word through a spell file's SOFO (sound-folding) byte map into a caller-owned result buffer. Its copy loop advances the output index ri with no upper bound and terminates only on the input NUL, writing one byte per input byte into the MAXWLEN-element stack buffer the caller provides. A word longer than MAXWLEN, passed to soundfold() (or reached via sound-based spell suggestion) while a SOFO-based spell language is active, therefore writes past the end of that buffer. This is a stack out-of-bounds write that corrupts the call frame and crashes the editor. This vulnerability is fixed in 9.2.0698.
— NVD
Vim: Stack out-of-bounds write in spellsoundfoldsofo() via an over-length soundfold() argument
— Microsoft
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 9.2.0735-1 - Upgrade
Upgrade
Vimto a version that resolves this vulnerability.Fixed in 9.2.0698
Event History
Frequently Asked Questions
What is the severity of CVE-2026-57455?
CVE-2026-57455 has a severity rating of medium with a CVSS score of 4.0.
How do I fix CVE-2026-57455?
To resolve CVE-2026-57455, upgrade Vim to version 9.2.0698 or later.
What vulnerability does CVE-2026-57455 address?
CVE-2026-57455 addresses a stack out-of-bounds write vulnerability in the `spell_soundfold_sofo()` function due to an over-length `soundfold()` argument.
What could happen if CVE-2026-57455 is exploited?
Exploitation of CVE-2026-57455 could lead to potential memory corruption and other security issues.
Which software is affected by CVE-2026-57455?
The affected software is Vim, specifically versions prior to 9.2.0698.