CVE-2026-59857 — Vim: Out-of-bounds Write in SAL Soundfolding

Vim is an open source, command line text editor. Prior to 9.2.0725, the single-byte branch of spell_soundfold_sal() in src/spell.c translates a word through a spell file's SAL sound-folding rules into a caller-owned result buffer, but its result writes are guarded with reslen < MAXWLEN, allowing reslen to reach MAXWLEN before res[reslen] = NUL writes one byte past the end of the MAXWLEN-element stack buffer. A boundary-length word passed to soundfold(), or reached via sound-based spell suggestion while a SAL-based spell language is active under a non-multibyte 8-bit encoding, can corrupt the eval_soundfold() stack frame and crash the editor. This issue is fixed in version 9.2.0725.

Published Jul 9, 2026Updated Jul 10, 2026Sources: cvelistV5, GitHub_M

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.

Exploitation

Unreported

no source claims exploitation

EPSS

chance of exploitation in 30 days

Affects

vim

CVSS base

5.6

MEDIUM

CISA SSVC assessment

Three decision points CISA publishes for the CVEs it assesses · SSVC 2.0.3. A stakeholder decision, not a severity score.

CISA

Exploitation

None

none · proof-of-concept · active

Automatable

can an attacker script all four kill-chain steps

Technical impact

Partial

partial · total control of the vulnerable component

Affected scope

The catalog records vendors and products as separate lists, not pairs, so which product belongs to which vendor is not something this page can say.

Vendors (1)

vim

Products (1)

vim

Every base score collected

Sources score independently and disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Source
5.6	CVSS 4.0	MEDIUM	—	—	cvelistV5

Weakness & attack patterns

CWE-787

Detection

Read off the CVSS vector and the weakness class. Starting points, not rules we have tested.

Search application, proxy, and WAF logs for requests touching /spell.c.

References

2 on the record

github.com/vim/vim/security/advisories/GHSA-m3hf-xcm3-xhm2
x_refsource_CONFIRM
github.com/vim/vim/commit/d22ff1c955ff87e8273210eae125aab0e85b6c30
x_refsource_MISC

Elsewhere on this site

vimevery CVE for this vendor
CWE-787other pages naming this weakness

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.