CVE-2025-59476

Description

In Jenkins 2.527 and earlier, LTS 2.516.2 and earlier, the log formatter that prepares log messages for console output (including `jenkins.log` and equivalent) does not restrict or transform the characters that can be inserted from user-specified content in log messages. This allows attackers able to control log message contents to insert line break characters, followed by forged log messages that may mislead administrators reviewing log output. Jenkins 2.528, LTS 2.516.3 adds an indicator at the beginning of a line that was inserted as part of log message content: `[CR]`, `[LF]`, or `[CRLF]` (representing the kind of line break), followed by `>` .

How to fix CVE-2025-59476

To remediate CVE-2025-59476, upgrade the affected package to a fixed version below.

• —upgrade to 2.516.3 or later
• —upgrade to 2.516.3 or later

Is CVE-2025-59476 being exploited?

Low — EPSS is 0.1%, meaning exploitation activity has not been observed at scale.

Affected packages (2)

• from 0, < 2.516.3, >= 2.517.0, < 2.528.0
• from 0, < 2.516.3

CVSS scores

References (4)

• ADVISORYnvd.nist.gov/vuln/detail/CVE-2025-59476
• PATCHgithub.com/jenkinsci/jenkins
• WEBwww.jenkins.io/security/advisory/2025-09-17/#SECURITY-3424
• WEBwww.openwall.com/lists/oss-security/2025/09/17/1