Review reviewHigh

CVE-2026-10513

pfefferle Webmention

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 (m...

CVSS: 7.2
EPSS: 0.24%
CISA KEV: Not listed
Published: 2026.07.01

PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV

Exploit probability0.24%

Technical severityCVSS 7.2

Vulnerability overview

Affected product and versions

Product: pfefferle Webmention
Affected versions: See the vendor advisory and NVD configuration data
Fixed versions: No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide

1
Identify
Confirm that pfefferle Webmention and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
CWE: CWE-79