🛡️ CVE-2016-4000 — jython

🔴 CVSS 9.5 — Critical ✅ No Known Exploit CWE-502 OSV
9.5
CVSS Score
0 Low4 Medium7 High9 Critical10

Description

Deserialization of Untrusted Data in Jython

Jython before 2.7.1b3 allows attackers to execute arbitrary code via a crafted serialized PyFunction object.

How this vulnerability can be exploited

This issue can be reached over the network, attack complexity is low, an attacker needs no privileges on the target. No user interaction is required. The scope is unchanged, so the impact stays within the vulnerable component. Rated impact: confidentiality high, integrity high, availability high.

Weakness class

CVE-2016-4000 is classified as CWE-502: Deserialization of Untrusted Data. Serialised data from an untrusted source is reconstructed into objects, which can trigger code during the process.

Affected software

CVE-2016-4000 is recorded against 2 packages.

  • org.python:jython (fixed in 2.7.1b3)
  • org.python:jython-standalone (fixed in 2.7.1b3)

Timeline and source

Published on 13 May 2022 and last revised on 2 July 2026. No public exploit is currently recorded for this entry. Record sourced from OSV.

References

nvd.nist.gov (Advisory)
github.com (Web)
www.oracle.com (Web)
www.oracle.com (Web)
www.oracle.com (Web)
www.oracle.com (Web)
www.oracle.com (Web)
www.oracle.com (Web)
snyk.io (Web)
security.gentoo.org (Web)
security-tracker.debian.org (Web)
lists.apache.org (Web)
hg.python.org (Web)
hg.python.org (Web)
github.com (Package)

Details

Severity CRITICAL
CVSS Score 9.5
CVSS Vector CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE CWE-502
Public Exploit ✅ No
Source OSV
Published 2022-05-13
Updated 2026-08-12
Modified 2026-07-02
Fix URL N/A

Affected Packages

Software From version Fixed in
org.python:jython — 2.7.1b3
org.python:jython-standalone — 2.7.1b3

References

Similar Threats

Exploit Protection

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