CVE-2026-59856
CVE-2026-59856 — Vim: Arbitrary Code Execution via PHP Omni-Completion
Vim is an open source, command line text editor. Prior to 9.2.0736, the PHP omni-completion script in runtime/autoload/phpcomplete.vim interpolates a class or trait name, taken from the contents of the edited buffer, into a search() pattern that is run via win_execute() without escaping. A name containing a single quote can terminate the search() string argument early, and because the bar is honored as an Ex command separator, the remainder of the name is run as Ex commands; via the :! command this allows arbitrary operating-system command execution when a victim opens a crafted PHP file and invokes omni-completion. This issue is fixed in version 9.2.0736.
Published Updated Sources: 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
0%
chance of exploitation in 30 days
CVSS base
8.4
HIGH
CISA SSVC assessment
Three decision points CISA publishes for the CVEs it assesses · SSVC 2.0.3. A stakeholder decision, not a severity score.
Exploitation
None
none · proof-of-concept · active
Automatable
No
can an attacker script all four kill-chain steps
Technical impact
Total
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)
Products (1)
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 |
|---|---|---|---|---|---|
| 8.4 | CVSS 4.0 | HIGH | — | — | cvelistV5 |
Weakness & attack patterns
- CWE-94
Attack patterns reported against this CVE. The ATT&CK techniques below are inferred from its weakness class.
- T1027.006Obfuscated Files or Information: HTML Smuggling
- T1027.009Obfuscated Files or Information: Embedded Payloads
- T1564.009Hide Artifacts: Resource Forking
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 /autoload/phpcomplete.vim.
References
2 on the record
- github.com/vim/vim/security/advisories/GHSA-fh26-8f79-wj97
x_refsource_CONFIRM
- github.com/vim/vim/commit/43afc581a37a35762dd0ef292f038b9dc5680a24
x_refsource_MISC
Elsewhere on this site
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.