Subscriber-level file overwrite via snippets path traversal
Published Apr 10, 2026 · Updated Apr 10, 2026
Path traversal in Perfmatters 2.5.9 and earlier allows remote authenticated users to overwrite server files through snippet bulk actions. PMCS::action_handler accepts unsanitized snippets[] paths for activate or deactivate without authorization or nonce validation, and Snippet::update passes the traversed path to file_put_contents. Subscriber-level access is sufficient; writes contain a fixed PHP docblock and can interrupt the WordPress site by corrupting .htaccess or index.php.
Summary
What happened
Path traversal in Perfmatters 2.5.9 and earlier allows remote authenticated users to overwrite server files through snippet bulk actions. PMCS::action_handler accepts unsanitized snippets[] paths for activate or deactivate without authorization or nonce validation, and Snippet::update passes the traversed path to file_put_contents. Subscriber-level access is sufficient; writes contain a fixed PHP docblock and can interrupt the WordPress site by corrupting .htaccess or index.php.
The record
- CVE
- CVE-2026-4351
- Published
- Apr 10, 2026
- Updated
- Apr 10, 2026
- Vendor
- forgemedia LLC
- Product
- Perfmatters
- Classifications
- CWE-22, T1499.004
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Apr 10, 2026CVE publishedPublication date reported by the CVE source.
- Apr 10, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0 <=2.5.9
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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