Objenesis before 3.6 contains a type confusion vulnerability that allows code in one class loader to substitute
Affects objenesisSource GCVE Database
Not known to be exploited · CVSS 2.0 Low : update objenesis when convenient.
Data as of 28 Oct 2026, 22:42 UTC
CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 26 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Patches and advisories
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.10objenesispkg:deb/ubuntu/objenesis?arch=source&distro=stonkingOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSobjenesispkg:deb/ubuntu/objenesis?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSobjenesispkg:deb/ubuntu/objenesis?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 22.04 LTSobjenesispkg:deb/ubuntu/objenesis?arch=source&distro=jammyOther threats | Affected
| Fixed in– |
Ubuntu 20.04 LTSobjenesispkg:deb/ubuntu/objenesis?arch=source&distro=focalOther threats | Affected
| Fixed in– |
Ubuntu 18.04 LTSobjenesispkg:deb/ubuntu/objenesis?arch=source&distro=bionicOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A fix is available. Users should upgrade to Objenesis version 3.6 or later. Refer to the Debian security tracker advisory for patch details: https://security-tracker.debian.org/tracker/cve-2026-116486.
Description
Objenesis versions before 3.6 have a type confusion vulnerability due to instantiator caching keyed on class name, which can cause objects from one class loader to be substituted into another. This leads to ClassCastException failures when newInstance() returns objects of the wrong class.
References
- ubuntu.com/security/CVE-2026-116486 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-116486 (opens in a new tab)
- github.com/cveproject/cvelistv5/tree/main/cves/2026/116xxx/cve-2026-116486.json (opens in a new tab)
- github.com/easymock/objenesis (opens in a new tab)
- github.com/easymock/objenesis/blob/fb36e5c377ed1bf57a18386fa79d2eed4ddfcfac/main/src/main/java/org/objenesis/objenesisbase.java (opens in a new tab)
- github.com/easymock/objenesis/commit/40f90f435a06b16af74a7398f0007faeaa52c00c (opens in a new tab)
- github.com/easymock/objenesis/security/advisories/ghsa-743r-26gf-97ff (opens in a new tab)
- nvd.nist.gov/vuln/detail/cve-2026-116486 (opens in a new tab)
- security-tracker.debian.org/tracker/cve-2026-116486 (opens in a new tab)
- vulncheck.com/advisories/objenesis-before-3.6-type-confusion-via-class-name-instantiator-cache (opens in a new tab)