---
title: "CVE-2026-55693\n    | Ubuntu"
description: Ubuntu is an open source software operating system that runs from the
  desktop, to the cloud, to all your internet connected things.
url: https://ubuntu.com/security/CVE-2026-55693?format=md
keywords: index, follow
---

# CVE-2026-55693

Publication date 25 June 2026

Last updated 2 July 2026

---

Ubuntu priority

**Medium**

[Why this priority?](https://ubuntu.com/security/cves/about#priority )

## Cvss 3 Severity Score

**7.8 · High**

[Score breakdown](https://ubuntu.com/security/CVE-2026-55693?format=md#impact-score)

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## 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.

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| vim | 26.04 LTS resolute | Fixed 2:9.1.2141-1ubuntu4.6 |
| 25.10 questing | Fixed 2:9.1.0967-1ubuntu6.8 |
| 24.04 LTS noble | Fixed 2:9.1.0016-1ubuntu7.17 |
| 22.04 LTS jammy | Fixed 2:8.2.3995-1ubuntu2.33 |
| 20.04 LTS focal | Fixed 2:8.1.2269-1ubuntu5.32+esm9  Ubuntu Pro |
| 18.04 LTS bionic | Fixed 2:8.0.1453-1ubuntu1.13+esm21  Ubuntu Pro |
| 16.04 LTS xenial | Fixed 2:7.4.1689-3ubuntu1.5+esm36  Ubuntu Pro |
| 14.04 LTS trusty | Fixed 2:7.4.052-1ubuntu3.1+esm30  Ubuntu Pro |

---

* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)
* [Patch details](https://ubuntu.com/security/CVE-2026-55693?format=md#patch-details)

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### Patch details

For informational purposes only. We recommend not to cherry-pick updates. [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)

| Package | Patch details |
| --- | --- |
| vim | * Upstream:   [a80874d](https://github.com/vim/vim/commit/a80874d9b84a01040e3d1aef2d4a59e1934dafb7) |

## Severity score breakdown

CVSS version:

CVSS v4.0

[CVSS v4.0](https://ubuntu.com/security/CVE-2026-55693?format=md)
[CVSS v3.0](https://ubuntu.com/security/CVE-2026-55693?format=md)

**Base score**

5.7 · Medium

* Base metrics

  | Parameter | Value |
  | --- | --- |
  | Attack vector | Local |
  | Attack complexity | Low |
  | Attack requirements | None |
  | Privileges required | None |
  | User interaction | Active |
  | Vulnerable system - Confidentiality impact | High |
  | Vulnerable system - Integrity impact | High |
  | Vulnerable system - Availability impact | High |
  | Subsequent system - Confidentiality impact | None |
  | Subsequent system - Integrity impact | None |
  | Subsequent system - Availability impact | None |
* Scores

  | Parameter | Value |
  | --- | --- |
  | Base score | 5.7 · Medium |
  | Base + Threat score | - |
  | Base + Environmental score | - |
  | Base + Threat + Environmental score | - |

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

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-55693)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2026-55693)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2026-55693)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2026-55693)

### Related Ubuntu Security Notices (USN)

+ [USN-8500-1](https://usn.ubuntu.com/USN-8500-1)
+ Vim vulnerabilities
+ 2 July 2026

### Other references

* <https://www.cve.org/CVERecord?id=CVE-2026-55693>
* <https://github.com/vim/vim/security/advisories/GHSA-wgh4-64f7-q3jq>