CVE-2026-10513

Webmention <= 5.8.0 - Unauthenticated Stored Cross-Site Scripting via MF2 'photo'/'url' Author Properties

HIGH
7.2
CVSS Score
Published: June 30, 2026 at 06:32 PM UTC
Updated: July 2, 2026 at 01:52 AM UTC
1 product affected across 1 vendorWebmention

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Severity
HIGH7.2
Exploit prediction
EPSS 0.4%
SSVC
No known 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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Webmention· Pfefferlewordpress-plugin
60%
v ≤ 5.8.0

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.2HIGHWordfence
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-79

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