CyberSecBulletin
CVE-2026-53435NVD status: Modified

Jenkins: Deserialization of Untrusted Data

Published Updated By the CyberSecBulletin desk

CVE-2026-53435 is a high-severity deserialization of untrusted data vulnerability in Jenkins, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. There is no confirmed exploitation so far. EPSS estimates a 51.2% chance of exploitation within 30 days, which is in the top 1.05% of all scored CVEs.

Patch now

Exploitation in the next 30 days is more likely than not, according to EPSS.

What to do

  1. Check which version of Jenkins you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on jenkins.io for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
Jenkins ProjectJenkinsNot specified in the recordNot stated
Red HatOpenShift Developer Tools and Services 4.12Not specified in the recordNot stated
Red HatOpenShift Developer Tools and Services 4.13Not specified in the recordNot stated
Red HatOpenShift Developer Tools and Services 4.14Not specified in the recordNot stated
Red HatOpenShift Developer Tools and Services 4.15Not specified in the recordNot stated
Red HatOpenShift Developer Tools and Services 4.16Not specified in the recordNot stated
Red HatOpenShift Developer Tools and Services 4.17Not specified in the recordNot stated
Red HatOpenShift Developer Tools and Services 4.18Not specified in the recordNot stated
Red HatOpenShift Developer Tools and Services 4.19Not specified in the recordNot stated
Red HatOpenShift Developer Tools and Services 4.20Not specified in the recordNot stated
Red HatOpenShift Developer Tools and Services 4.21Not specified in the recordNot stated
Red HatOpenShift Developer Tools and Services 4.22Not specified in the recordNot stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by CNA.

Scoring systemScoreSeverityScored by
CVSS 3.18.8HighCISA (ADP)
CVSS 3.18.8HighCNA

Official description

In Jenkins 2.567 and earlier, LTS 2.555.2 and earlier, it is possible for attackers to have Jenkins deserialize arbitrary types defined in Jenkins core or plugins from an attacker-controlled `config.xml` submission in a way that allows them to handle HTTP requests afterwards. This can be used to impersonate any user and send HTTP requests on their behalf, up to and including use of the Script Console to run arbitrary code, or to read arbitrary files from the Jenkins controller.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Deserialization of Untrusted Data

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

How developers prevent this class of flaw

  • If available, use the signing/sealing features of the programming language to assure that deserialized data has not been tainted. For example, a hash-based message authentication code (HMAC) could be used to ensure that data has not been modified.
  • When deserializing data, populate a new object rather than just deserializing. The result is that the data flows through safe input validation and that the functions are safe.
  • Explicitly define a final object() to prevent deserialization.

More Deserialization of Untrusted Data vulnerabilities (CWE-502)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Jenkins

All Jenkins vulnerabilities

Recent Deserialization of Untrusted Data vulnerabilities

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