Vulnerability in WP Compress – Instant Performance & Speed Optimization — WF-42d4ec8b-d3ed-4aa3-a8b9-cddaf64a7531
What to do now
Update WP Compress – Instant Performance & Speed Optimization to 7.22.38 or later.
Affected versions
- Everything up to and including 7.22.01
Affected: WP Compress – Instant Performance & Speed Optimization (plugin, wp-compress-image-optimizer)
What the vulnerability is
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.