Webmention <= 5.6.2 - Unauthenticated Blind Server-Side Request Forgery
Priority LOW 37CWE-918Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- Low · Low · None
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA.
Summary
The Webmention plugin for WordPress is vulnerable to Server-Side Request Forgery in all versions up to, and including, 5.6.2 in the 'MF2::parse_authorpage' function via the 'Receiver::post' function. This makes it possible for unauthenticated attackers to make web requests to arbitrary locations originating from the web application and can be used to query and modify information from internal services.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00314 24th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2026-0686
- 2026-10-03 Alias added: GHSA-pwm7-wr54-2jxv
References
Other 5
- https://www.wordfence.com/threat-intel/vulnerabilities/id/08d15c46-d15f-4803-80be-90bf33335c18?source=cve
- https://github.com/pfefferle/wordpress-webmention/blob/057223cee18a9e93b017d0f21db6ea77a7686489/includes/handler/class-mf2.php#L878
- https://plugins.trac.wordpress.org/browser/webmention/tags/5.6.2/includes/handler/class-mf2.php#L877
- https://plugins.trac.wordpress.org/browser/webmention/tags/5.6.2/includes/class-receiver.php#L260
- https://plugins.trac.wordpress.org/changeset/3494831/webmention
More pfefferle vulnerabilities
- TI-2026-09044 Webmention <= 5.8.0 - Unauthenticated Stored Cross-Site Scripting via MF2 'photo'/'url' Author Properties CVSS 3.1HIGH 7.2
- TI-2026-00480 Webmention <= 5.6.2 - Authenticated (Subscriber+) Server-Side Request Forgery CVSS 3.1MEDIUM 6.4
- TI-2026-83489 Stored cross-site scripting in Webmention plugin for WordPress CVSS 3.1MEDIUM 6.1
Sources
- CVE-2026-0686 · CVE Program
- CVE-2026-0686 · NVD
- FIRST EPSS
- GHSA-pwm7-wr54-2jxv · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences