CVE-2026-80428CWE-502insecure-deserialization

CVE-2026-80428

Critical · published August 26, 2026

CVSS v3.1
9.8
EPSS
5%
Percentile
91.7
In the wild
Unconfirmed
What it is

ILIAS before versions 9.22, 10.10, and 11.3 contains an unauthenticated PHP object injection vulnerability that allows unauthenticated attackers to execute arbitrary code by injecting serialized objects through the LTI authentication endpoint and triggering deserialization via the Shibboleth back-channel logout endpoint. Attackers can write arbitrary serialized objects into session storage, then exploit an available POP gadget through the logout endpoint's unrestricted deserialization to write attacker-controlled PHP content to a web-accessible path and achieve remote code execution as the web server user.

The record
Technical detail
CVSS v3.1
9.8 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
9.3 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
EPSS
0.04666 · 91.7th percentile
Weakness
CWE-502 · Deserialization of Untrusted Data
Published
2026-08-26T20:16Z
References (8)
EPSS history
Timeline
  • 28 AUG 06:54Z
    EPSS moved — → 1%
    epss
  • 26 AUG 15:44Z
    ILIAS before 9.22, 10.10 and 11.3 Unauthenticated PHP Object Injection via Shibboleth Logout Endpoint
    cvelistv5