CVE-2026-11976EPSS p42.3%

CVE-2026-11976CVE-2026-11976

Description

The official MonsterInsights Pro update distribution bucket (`monster-insights.s3.amazonaws.com`) was compromised. Both the current release (10.2.2) and the version MonsterInsights rolled back to (10.2.0) contain a malicious file, `class-system-check.php`. Three distinct variants were observed on 2026-06-11, all sharing the same AES-256-GCM key, confirming a single threat actor. The attacker retains write access to the S3 bucket and has been actively iterating on the payload throughout the day.

Scoring

CVSS 10.0 ()
VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
EPSS0.52% probability of exploitation · percentile 42.3% · 2026-10-05T12:00:23Z
Last modified2026-08-26
Sourced from NVD + FIRST.org EPSS. Curated for EU compliance use cases by Adam Lundqvist, Founder at SQUR.