CVE-2026-120551: WP Compress missing authorization check vulnerability
medium 5.3 published 2026-11-03
- Affected versions
- 7.22.01 and older
- Fixed in
- 7.22.38 *
- Latest version
- 7.30.45
- Severity
- Medium · CVSS 5.3
- Active installs
- 9,000+
- Type
- Missing authorization check
* The source does not name a fixed version; this is the first wordpress.org release after the last affected version.
What an attacker needs
- Access: None. No account or login is needed.
CVSS vector (score by Wordfence): CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
What to do now
- Update WP Compress to 7.22.38 or newer (the latest is 7.30.45): Dashboard → Updates, or Plugins → “update now”.
- If you cannot update right away, deactivate it until you can.
- Turn on auto-updates for it: Plugins → “Enable auto-updates” on its row.
- Not sure which version you run? Check your version against every known WP Compress issue.
With WP-CLI:
wp plugin get wp-compress-image-optimizer --field=version. - If you ran an affected version and something looks off (new admin users, spam pages, redirects), run the free scan below.
The advisory
The WP Compress – Instant Performance & Speed Optimization plugin for WordPress is vulnerable to authorization bypass in all versions up to, and including, 7.22.01. This is due to the plugin not properly verifying that a user is authorized to perform an action. This makes it possible for unauthenticated attackers to link the victim site to an attacker-controlled WP Compress account, overwrite plugin settings to an aggressive live-CDN preset, and gain the shared api_key that authenticates all nopriv HMAC-gated endpoints — enabling full control over cache purging, file deletion, opcode cache invalidation, and other privileged plugin operations. This vulnerability only affects fresh installations or lite/free-mode installs where no api_key is already stored, as the sole guard fails open when the stored key is absent.
References
- NVD CVE-2026-120551 nvd.nist.gov
- Wordfence advisory www.wordfence.com
- Code change (fix) plugins.trac.wordpress.org
- Plugin source plugins.trac.wordpress.org
Related
Ran an affected version? Check your site for signs of a hack
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Where this data comes from
- CVE record, score and references: NIST National Vulnerability Database (NVD), checked 2026-11-04. This product uses data from the NVD API but is not endorsed or certified by the NVD.
- Versions and install counts: wordpress.org/plugins/wp-compress-image-optimizer (Plugins API), fetched 2026-11-04.
- The summary, “what an attacker needs” and “what to do” sections are our plain-English reading of the record and the plugin's release history; the quoted description is the record's own text. Spot an error? Email Daniel.