Home

Description

The coreActivity: Activity Logging for WordPress plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 3.0. This is due to the plugin failing to validate or strip PHP serialization syntax from the User-Agent HTTP header before storing it in the logmeta table, and subsequently calling `maybe_unserialize()` on every retrieved `meta_value` in `query_metas()` without verifying the data was originally serialized by the application. This makes it possible for unauthenticated attackers to inject a crafted PHP serialized payload via the User-Agent header during any logged event (such as a failed login attempt), which, when an administrator views the Logs page, is deserialized and passed to `DeviceDetector::setUserAgent()`, triggering a Fatal TypeError that creates a persistent Denial of Service condition blocking administrator access to the Logs page entirely.

PUBLISHED Reserved 2026-05-01 | Published 2026-05-13 | Updated 2026-05-13 | Assigner Wordfence




HIGH: 8.1CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Problem types

CWE-502 Deserialization of Untrusted Data

Product status

Default status
unaffected

Any version
affected

Timeline

2026-05-02:Vendor Notified
2026-05-12:Disclosed

Credits

Duong Quang Hao finder

Thai Son Dinh finder

References

www.wordfence.com/...-6dd9-4367-90a9-a10ad491357d?source=cve

plugins.trac.wordpress.org/...ress/wordpress/admin/Table.php

plugins.trac.wordpress.org/...ress/wordpress/admin/Table.php

plugins.trac.wordpress.org/...tivity/trunk/core/log/Core.php

plugins.trac.wordpress.org/...ity/tags/3.0/core/log/Core.php

plugins.trac.wordpress.org/...4press/core/plugins/DBLite.php

plugins.trac.wordpress.org/...4press/core/plugins/DBLite.php

plugins.trac.wordpress.org/...vity/trunk/core/table/Logs.php

plugins.trac.wordpress.org/...y/tags/3.0/core/table/Logs.php

plugins.trac.wordpress.org/...vity/trunk/core/log/Device.php

plugins.trac.wordpress.org/...y/tags/3.0/core/log/Device.php

github.com/...anges/1f09331d66de7cf4bba9b6e396b0d4e7597fcde2

cve.org (CVE-2026-7635)

nvd.nist.gov (CVE-2026-7635)

Download JSON