CVE-2026-55693
Vim: Out-of-bounds Write in Spell File Word Count
Description
Vim is an open source, command line text editor. Prior to 9.2.0653, the tree_count_words() function in src/spellfile.c fills in the word-count fields of a spell-file word trie by walking it iteratively with a depth counter. 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 (arridx[], curi[], wordcount[]). A crafted .spl/.sug file pair, loaded when the user invokes spell suggestion, 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 9.2.0653.
INFO
Published Date :
June 25, 2026, 4:16 p.m.
Last Modified :
June 26, 2026, 2:17 p.m.
Remotely Exploit :
No
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Update Vim to version 9.2.0653 or later.
- Avoid loading untrusted spell files.
- Validate spell file integrity before loading.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-55693.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-55693 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-55693
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-55693 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-55693 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 26, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-55693', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-06-26T14:02:19.096753Z'} -
Initial Analysis by [email protected]
Jun. 26, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Added CPE Configuration OR *cpe:2.3:a:vim:vim:*:*:*:*:*:*:*:* versions up to (excluding) 9.2.0653 Added Reference Type GitHub, Inc.: https://github.com/vim/vim/commit/a80874d9b84a01040e3d1aef2d4a59e1934dafb7 Types: Patch Added Reference Type GitHub, Inc.: https://github.com/vim/vim/releases/tag/v9.2.0653 Types: Product Added Reference Type GitHub, Inc.: https://github.com/vim/vim/security/advisories/GHSA-wgh4-64f7-q3jq Types: Vendor Advisory -
New CVE Received by [email protected]
Jun. 25, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'vim', 'product': 'vim', 'versions': [{'status': 'affected', 'version': '< 9.2.0653'}]}] Added Description Vim is an open source, command line text editor. Prior to 9.2.0653, the tree_count_words() function in src/spellfile.c fills in the word-count fields of a spell-file word trie by walking it iteratively with a depth counter. 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 (arridx[], curi[], wordcount[]). A crafted .spl/.sug file pair, loaded when the user invokes spell suggestion, 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 9.2.0653. Added CVSS V4.0 AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-787 Added Reference https://github.com/vim/vim/commit/a80874d9b84a01040e3d1aef2d4a59e1934dafb7 Added Reference https://github.com/vim/vim/releases/tag/v9.2.0653 Added Reference https://github.com/vim/vim/security/advisories/GHSA-wgh4-64f7-q3jq