CVE-2026-57289Network attack vector

Bearer token theft via disabled TLS validation

Published Jun 24, 2026 · Updated Jun 24, 2026

Improper certificate validation in Jenkins Bitbucket Push and Pull Request Plugin 3.3.8 and earlier allows attackers to capture Bearer tokens. Connections to configured Bitbucket Server endpoints unconditionally disable certificate-chain and hostname checks while transmitting Bearer tokens. Attackers who can intercept network traffic can read the token and impersonate the Jenkins controller to Bitbucket Server.

CVSS severity4.8
Medium
EPSS probability0.16%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper certificate validation in Jenkins Bitbucket Push and Pull Request Plugin 3.3.8 and earlier allows attackers to capture Bearer tokens. Connections to configured Bitbucket Server endpoints unconditionally disable certificate-chain and hostname checks while transmitting Bearer tokens. Attackers who can intercept network traffic can read the token and impersonate the Jenkins controller to Bitbucket Server.

The record

CVE
CVE-2026-57289
Published
Jun 24, 2026
Updated
Jun 24, 2026
Vendor
Jenkins Project
Product
Bitbucket Push and Pull Request
Classifications
CWE-295, T1557
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 24, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 24, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <=3.3.8

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Jenkins Project · Bitbucket Push and Pull Requestversion=0 <=3.3.8

Published CVSS scores

4.8CISA-ADPCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-295Improper Certificate Validation
T1557Adversary-in-the-Middle

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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