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CVE-2026-116486

CVE-2026-116486 · Objenesis before 3.6 Type Confusion via Class Name Instantiator Cache

This page contains facts from public vulnerability sources. Check the original advisory before updating.

Objenesis before 3.6 contains a type confusion vulnerability that allows code in one class loader to substitute objects into another by exploiting instantiator caching keyed on class name. When a shared ObjenesisStd instance caches instantiators by clazz.getName() in ObjenesisBase.getInstantiatorOf(), same-named classes collide, causing newInstance() to return wrong-class objects and ClassCastException failures.

CVSS 2.0 · Low · EPSS 0.1% · Fix available

Published
Updated

Stack: system

Affected products and versions

  • objenesis

    Versions
    • ≥ 0, < 3.6: Affected (custom)
    • 3.6: Not affected (custom)

    Update to 3.6

  • objenesis Debian:12

    Versions
    • 3.3-3
    • 3.4-1
    • 3.4-2
    • 3.5-1
    • 3.6-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • objenesis Debian:13

    Versions
    • 3.4-2
    • 3.5-1
    • 3.6-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • objenesis Debian:14

    Versions
    • 3.4-2
    • 3.5-1
    Affected ranges
    • ECOSYSTEM: < 3.6-1

    Update to 3.6-1

  • objenesis Ubuntu:14.04:LTS

    Versions
    • 1.2+full-3
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • objenesis Ubuntu:16.04:LTS

    Versions
    • 2.1-2
    • 2.2-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • objenesis Ubuntu:18.04:LTS

    Versions
    • 2.6-1
    • 3.0.1-2~18.04
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • objenesis Ubuntu:20.04:LTS

    Versions
    • 3.0.1-2
    • 3.1-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • objenesis Ubuntu:22.04:LTS

    Versions
    • 3.1-1
    • 3.2-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • objenesis Ubuntu:24.04:LTS

    Versions
    • 3.3-3
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • objenesis Ubuntu:26.10

    Versions
    • 3.5-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • objenesis Ubuntu:26.04:LTS

    Versions
    • 3.4-2
    • 3.4-2build1
    • 3.5-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

Original sources

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