CriticalCVE-2026-80428

    ILIAS PHP Object Injection via Shibboleth Logout (CVE-2026-80428)

    Published Last modified Sources: CVE.org

    What is affected, what to do

    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.

    An exploit is publicly available. Update ILIAS to version 9.22, ILIAS to version 10.10, ILIAS to version 11.3.

    Affected
    • ILIAS lt 9.0..9.22
    • ILIAS lt 10.0..10.10
    • ILIAS lt 11.0..11.3
    Fixed in
    • ILIAS 9.22
    • ILIAS 10.10
    • ILIAS 11.3

    Not sure whether and how you are affected? Ask a question about this vulnerability

    Metrics

    9.8

    Priority

    XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.

    Source: NVD, CVSS v3

    9.8

    CVSS v3

    Severity Critical on the scale from 0 to 10.

    Source: CVE.org

    4.7 %

    EPSS score

    Moderate — model estimates 1-10% exploitation likelihood.

    Source: FIRST EPSS, percentile 91.7

    Show all metrics
    Severity
    Critical
    Priority (0–325)

    The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first?

    Read in glossary
    140.62 Methodology
    Exploit maturity

    An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack.

    Read in glossary
    PoC (publicly reported)
    XIEM Effective CVSS

    XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command.

    Read in glossary
    9.8 Methodology
    CVSS v3

    CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions.

    Read in glossary
    9.8
    CVSS v4

    CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions.

    Read in glossary
    9.3
    EPSS score

    The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“.

    Read in glossary
    4.7 %
    Moderate — model estimates 1-10% exploitation likelihood.
    EPSS percentile

    The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking.

    Read in glossary
    91.7
    Critical — this CVE ranks in the top fifth of all CVEs scored today (rank ≥ 80%).
    KEV status

    The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.

    Read in glossary
    —
    Published
    CISA assessment (SSVC)
    Exploitation: none known · automatable · Technical impact: total
    Source: CISA Vulnrichment, as of 29 August 2026
    CWE

    CWE is a catalogue of typical weakness types in software and hardware — such as flawed input validation, unsafe memory handling or poor authentication. Where a CVE names a concrete vulnerability in a concrete product, a CWE describes the underlying class of defect.

    Read in glossary
    CWE-502

    Detection rules

    No NEOSEC detection rule is available for this vulnerability yet.

    Classification under NIS2 and CRA

    Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.

    NIS2

    NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.

    Read in glossary
    High technical severity: assess and remediate the vulnerability in vulnerability handling under Art. 21(2)(e) NIS2 and document the decision.
    CRA

    The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.

    Read in glossary
    From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
    ISO/IEC 27001

    ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.

    Read in glossary
    Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.

    Description

    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.

    Source: NVD (NIST), cvelistv5

    Affected products

    The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.

    Affected products
    Affected versionsFixed in
    ILIAS-eLearning e.V.ILIAS
    • 11.0 – < 11.3
    • 10.0 – < 10.10
    • 9.0 – < 9.22
    • 11.3
    • 10.10
    • 9.22

    Vendors and products

    Weakness classes (CWE)

    • CWE-502Deserialization of Untrusted Data

      Base

      The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.

      Entry at MITRE CWE-502

    Public exploit references

    Publicly reported proof-of-concepts, exploit modules and detection templates for this vulnerability. NEOSEC links to the original sources only and does not provide any exploit code.

    Public exploit references
    PoC-in-GitHub (nomi-sec)CVE-2026-80428 (opens in a new tab)github.comPoC (publicly reported)reported, not verified
    PoC-in-GitHub (nomi-sec)CVE-2026-80428 (opens in a new tab)github.comPoC (publicly reported)reported, not verified
    PoC-in-GitHub (nomi-sec)CVE-2026-80428 (opens in a new tab)github.comPoC (publicly reported)reported, not verified

    References & sources

    Changes to this CVE

    Who changed this CVE and when: NVD (analysis, affected products, CVSS), the CVE publisher (CNA) and additional providers such as CISA (ADP).

    1. Record modifiedVulnCheck

      Show 2 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Referenceadded
      —
      https://schweigertit.de/en/advisories/SIT-2026-002.html
      Referenceadded
      —
      https://schweigertit.de/en/writeups/php-object-injection-shibboleth-logout.html

      Source identifier: disclosure@vulncheck.com

    2. Record modifiedVulnCheck

      Description added or changed

      Show 11 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Descriptionchanged
      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.
      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.
      Affected versions (publisher)added
      —
      Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/80xxx/CVE-2026-80428.json">CVE-2026-80428</a>
      Referenceadded
      —
      https://docu.ilias.de/ilias.php?baseClass=illmpresentationgui&obj_id=225630&ref_id=35
      Referenceadded
      —
      https://docu.ilias.de/ilias.php?baseClass=illmpresentationgui&obj_id=225631&ref_id=35
      Referenceadded
      —
      https://docu.ilias.de/ilias.php?baseClass=illmpresentationgui&obj_id=225632&ref_id=35
      Referenceadded
      —
      https://docu.ilias.de/ilias.php?baseClass=ilrepositorygui&cmdNode=wy:ll:6t&cmdClass=ilBlogPostingGUI&cmd=previewFullscreen&ref_id=15821&blpg=934
      Referenceadded
      —
      https://docu.ilias.de/ilias.php?baseClass=ilrepositorygui&cmdNode=wy:ll:6t&cmdClass=ilBlogPostingGUI&cmd=previewFullscreen&ref_id=15821&blpg=935
      Referenceadded
      —
      https://docu.ilias.de/ilias.php?baseClass=ilrepositorygui&cmdNode=wy:ll:6t&cmdClass=ilBlogPostingGUI&cmd=previewFullscreen&ref_id=15821&blpg=936
      Referenceremoved
      https://github.com/ILIAS-eLearning/ILIAS
      —
      Referenceremoved
      https://github.com/ILIAS-eLearning/ILIAS/commit/f36934a6f937d0fe837ca6e642986458b4069a95
      —
      Referenceremoved
      https://www.vulncheck.com/advisories/ilias-before-9.22-10.10-and-11.3-unauthenticated-php-object-injection-via-shibboleth-logout-endpoint
      —

      Source identifier: disclosure@vulncheck.com

    3. Record modifiedCISA ADP

      CISA assessment (SSVC): exploitation: none known, automatable: yes

      Show the original change
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      SSVC assessmentadded
      —
      {"id":"CVE-2026-80428","role":"CISA Coordinator","options":[{"exploitation":"none"},{"automatable":"yes"},{"technicalImpact":"total"}],"version":"2.0.3","timestamp":"2026-08-29T02:41:22.173954Z"}

      Source identifier: 134c704f-9b21-4f2e-91b3-4a467353bcc0

    4. ReceivedVulnCheck

      CVSS V4.0: AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

      CVSS V3.1: AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

      Weakness type: CWE-502

      Description added or changed

      Show 8 original changes
      Individual changes of this event as published by NVD
      TypeActionBeforeAfter
      Descriptionadded
      —
      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.
      CVSSadded
      —
      AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
      CVSSadded
      —
      AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
      Weakness type (CWE)added
      —
      CWE-502
      Affected versions (publisher)added
      —
      New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/80xxx/CVE-2026-80428.json">CVE-2026-80428</a>
      Referenceadded
      —
      https://github.com/ILIAS-eLearning/ILIAS
      Referenceadded
      —
      https://github.com/ILIAS-eLearning/ILIAS/commit/f36934a6f937d0fe837ca6e642986458b4069a95
      Referenceadded
      —
      https://www.vulncheck.com/advisories/ilias-before-9.22-10.10-and-11.3-unauthenticated-php-object-injection-via-shibboleth-logout-endpoint

      Source identifier: disclosure@vulncheck.com

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