CVE-2026-55892: Vim is an open source, command line text editor. Prior to 9.2.0662, the dump_prefixes() function in src/spell.c walks a spell-file prefix trie iterati...

Description

Vim is an open source, command line text editor. Prior to 9.2.0662, the dump_prefixes() function in src/spell.c walks a spell-file prefix trie iteratively with a depth counter while dumping the prefixes that apply to a word. The counter is bounded only by the trie structure itself; it is never checked against the size of the fixed MAXWLEN-element stack arrays it indexes (prefix[], arridx[], curi[]). A crafted .spl file, loaded when the user dumps the word list, can drive the descent arbitrarily deep, so the function writes past the end of those arrays. This is a stack out-of-bounds write that corrupts the call frame and crashes the editor. This vulnerability is fixed in 9.2.0662.

Metrics

CVSS 3.1

5.5/10

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

EPSS Probability

0.12%

2.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-787

Affected Software

Vendor	Product	Versions
Vim	Vim	< 9.2.0662

References

Timeline

Published: Jun 25, 2026
Last Modified: Jun 26, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-55892?

Vim is an open source, command line text editor. Prior to 9.2.0662, the dump_prefixes() function in src/spell.c walks a spell-file prefix trie iteratively with a depth counter while dumping the prefixes that apply to a word. The counter is bounded only by the trie structure itself; it is never checked against the size of the fixed MAXWLEN-element stack arrays it indexes (prefix[], arridx[], curi[]). A crafted .spl file, loaded when the user dumps the word list, can drive the descent arbitrarily deep, so the function writes past the end of those arrays. This is a stack out-of-bounds write that corrupts the call frame and crashes the editor. This vulnerability is fixed in 9.2.0662.

How severe is CVE-2026-55892?

CVE-2026-55892 has a CVSS score of 5.5/10 (MEDIUM severity). The EPSS model estimates a 0.12% probability of exploitation in the next 30 days.

How do I fix CVE-2026-55892?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.