CyberSecBulletin
CVE-2025-32755NVD status: Analyzed

Jenkins jenkins/ssh-slave Docker images: Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)

CVE-2025-32755 is a critical-severity use of cryptographically weak pseudo-random number generator (PRNG) vulnerability in Jenkins jenkins/ssh-slave Docker images from Jenkins, with a CVSS 3.1 base score of 9.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. There is no confirmed exploitation so far. EPSS estimates a 0.49% chance of exploitation within 30 days, which is low compared with other CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of Jenkins jenkins/ssh-slave Docker images 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.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Jenkins ProjectJenkins jenkins/ssh-slave Docker imagesNot specified in the recordNot stated
JenkinsSsh-slaveNot 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
NoneNo account or login is needed.
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
NoneAvailability is not affected.

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

Official description

In jenkins/ssh-slave Docker images based on Debian, SSH host keys are generated on image creation for images based on Debian, causing all containers based on images of the same version use the same SSH host keys, allowing attackers able to insert themselves into the network path between the SSH client (typically the Jenkins controller) and SSH build agent to impersonate the latter.

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

The underlying weakness: Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)

The product uses a Pseudo-Random Number Generator (PRNG) in a security context, but the PRNG's algorithm is not cryptographically strong.

How developers prevent this class of flaw

  • Use functions or hardware which use a hardware-based random number generation for all crypto. This is the recommended solution. Use CyptGenRandom on Windows, or hw_rand() on Linux.

More Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG) vulnerabilities (CWE-338)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG) vulnerabilities

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