CVE-2026-0686 json
Webmention <= 5.6.2 - Unauthenticated Blind Server-Side Request Forgery
published 7mo ago modified 4mo ago also EUVD-2026-18132
- cvss
- 7.2
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 24%
- public exploits
- 0
- none known
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.
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 7mo ago
Exploit prediction
0.31% chance of exploitation in the next 30 days, higher than 24% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.2 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N |
Affected products
- pfefferle Webmention
Classification
- Weakness
-
- CWE-918 Server-Side Request Forgery
- Technology feeds
References
- wordfence.com /threat-intel/vulnerabilities/id/08d15c46-d15f-4803-80be-90bf33335c18?source=cve
- github.com /pfefferle/wordpress-webmention/blob/057223cee18a9e93b017d0f21db6ea77a7686489/includes/handler/class-mf2.php#L
- plugins.trac.wordpress.org /browser/webmention/tags/5.6.2/includes/handler/class-mf2.php#L877
- plugins.trac.wordpress.org /browser/webmention/tags/5.6.2/includes/class-receiver.php#L260
- plugins.trac.wordpress.org /changeset/3494831/webmention
Sources
- CVE List CVE-2026-0686
- NVD CVE-2026-0686
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.