ILIAS-eLearning ILIAS up to 9.21/10.9/11.2 Shibboleth Logout shib_logout.php unserialize deserialization

Summaryinfo

A vulnerability classified as critical has been found in ILIAS-eLearning ILIAS up to 9.21/10.9/11.2. This impacts the function unserialize of the file components/ILIAS/AuthShibboleth/resources/shib_logout.php of the component Shibboleth Logout Handler. Performing a manipulation results in deserialization. This vulnerability is reported as CVE-2026-80428. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability, which was classified as critical, was found in ILIAS-eLearning ILIAS up to 9.21/10.9/11.2. This affects the function unserialize of the file components/ILIAS/AuthShibboleth/resources/shib_logout.php of the component Shibboleth Logout Handler. The manipulation with an unknown input leads to a deserialization vulnerability. CWE is classifying the issue as CWE-502. The product deserializes untrusted data without sufficiently verifying that the resulting data will be valid. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

ILIAS deserialises stored session data for an unauthenticated caller. The Shibboleth back-channel endpoint at components/ILIAS/AuthShibboleth/resources/shib_logout.php runs in a context that ilInitialisation exempts from authentication, and its logout-notification handler locates the session to terminate by reading every live row of the session table and passing each row's stored data to a hand-written parser that calls unserialize without restricting which classes may be constructed. Any serialised object present in any session row is therefore instantiated on behalf of an anonymous request, and object destructors run when those objects are discarded. A serialised object can be placed into a session row without logging in, because the LTI authentication entry point stores request parameters into the session and is reachable on a path the same initialisation code exempts from authentication. A class bundled with the application writes a JSON-encoded structure to a file named by one of its own properties when it is destroyed, which places attacker-controlled content at an attacker-chosen path below the web root and results in code execution as the web server user. Versions 9.22, 10.10 and 11.3 remove the endpoint's logout-notification implementation.

The advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2026-80428 since 08/26/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details are known, but no exploit is available.

By approaching the search of inurl:components/ILIAS/AuthShibboleth/resources/shib_logout.php it is possible to find vulnerable targets with Google Hacking.

Upgrading to version 9.22, 10.10 or 11.3 eliminates this vulnerability.

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Vendor

• ILIAS-eLearning

Name

• ILIAS

Version

• 9.0
• 9.1
• 9.2
• 9.3
• 9.4
• 9.5
• 9.6
• 9.7
• 9.8
• 9.9
• 9.10
• 9.11
• 9.12
• 9.13
• 9.14
• 9.15
• 9.16
• 9.17
• 9.18
• 9.19
• 9.20
• 9.21
• 10.0
• 10.1
• 10.2
• 10.3
• 10.4
• 10.5
• 10.6
• 10.7
• 10.8
• 10.9
• 11.0
• 11.1
• 11.2

License

• open-source

CPE 2.3info

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CPE 2.2info

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