CVE-2026-10513
The Webmention plugin for WordPress is vulnerable to Stored Cross-Site Scripting in versions up to and including 5.8.0 via parser-derived 'avatar' and 'url' author metadata.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.40%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
The Webmention plugin for WordPress is vulnerable to Stored Cross-Site Scripting in versions up to and including 5.8.0 via parser-derived 'avatar' and 'url' author metadata. This is due to insufficient input sanitization and output escaping on user-supplied MF2 author properties processed by the unauthenticated webmention REST endpoint and rendered directly into HTML 'value' attributes by the edit-comment-form template without esc_attr() or esc_url(). This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a privileged user (moderator or administrator) opens the affected comment edit screen.
- CVSS 3.1
- 7.2 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
- EPSS
- 0.40% probability · 35th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-79
- Source
- security@wordfence.com
EPSS 0.4% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://plugins.trac.wordpress.org/browser/webmention/tags/5.7.0/includes/handler/class-mf2.php#L129
- https://plugins.trac.wordpress.org/browser/webmention/tags/5.7.0/templates/edit-comment-form.php#L15
- https://plugins.trac.wordpress.org/changeset/3583033/webmention
- https://www.wordfence.com/threat-intel/vulnerabilities/id/5a4e144a-3c84-4da3-8fa6-e5fe9c897efe?source=cve
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.