CVE-2026-104755
Vulnérabilité moyenne dans WP Compress – Instant Performance & Speed Optimization (aresit)
Description
The WP Compress – Instant Performance & Speed Optimization plugin for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 7.25.00 The vulnerability exists because the `start_comms` dispatcher (`wps_ic_comms::start_comms`), hooked on every front-end request, gates access only by comparing the caller-supplied `apikey` parameter against the stored plugin API key with no WordPress capability check and no nonce verification, then passes the unvalidated `group`, `setting`, and `value` parameters directly to `change_setting()`, which writes them into the `WPS_IC_SETTINGS` option without an allow-list. This makes it possible for unauthenticated attackers to write arbitrary permission keys into the plugin's settings, causing `wps_ic_users::checkAndAddCaps()` to grant any WordPress role — including Subscriber — the `manage_wpc_settings` capability and thereby achieve plugin-administrator-equivalent control over the plugin's optimization, CDN, and critical-CSS surfaces. The API key required to pass the authorization check can itself be obtained without authentication via the `wpc_send_critical_remote` nopriv AJAX action: when the external critical-CSS service returns an `apiResults` field, `initCritical()` echoes the stored plugin API key back to the caller in a `wp_send_json_success` response, completing the exploit chain entirely without a WordPress login.
Gravité et risque d'exploitation
CVE-2026-104755 obtient un score CVSS de 4.8/10, soit une gravité moyenne. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.31 %, ce qui la place devant 22.4 % des CVE référencées.
Que faire ?
- Vérifiez si WP Compress – Instant Performance & Speed Optimization (versions <=7.25.00, 0) est présent sur votre parc.
- Appliquez le correctif ou la version corrigée indiqués dans les références de l'éditeur.
- À défaut de correctif, limitez l'exposition (filtrage réseau, désactivation du composant).
- Automatisez la détection : les agents CVE Heimdall (gratuits, open source) corrèlent l'inventaire de vos serveurs avec la base CVE.
Références
- https://www.wordfence.com/threat-intel/vulnerabilities/id/67e9bfb8-b274-422a-a50d-a6b6b24bb193?source=cve
- https://plugins.trac.wordpress.org/browser/wp-compress-image-optimizer/tags/7.10.03/classes/comms.class.php#L49
- https://plugins.trac.wordpress.org/browser/wp-compress-image-optimizer/tags/7.10.03/classes/users.class.php#L30
- https://plugins.trac.wordpress.org/browser/wp-compress-image-optimizer/tags/7.10.03/classes/comms.class.php#L1042
- https://plugins.trac.wordpress.org/browser/wp-compress-image-optimizer/tags/7.10.03/classes/ajax.class.php#L816
- https://plugins.trac.wordpress.org/browser/wp-compress-image-optimizer/tags/7.10.03/addons/criticalCss/criticalCss.php#L409
- https://plugins.trac.wordpress.org/changeset?reponame=&new=3734610%40wp-compress-image-optimizer%2Ftags%2F7.26.00&old=3723132%40wp-compress-image-optimizer%2Ftags%2F7.25.00