Phishing via unchecked post-login redirect target
Published Jun 10, 2026 · Updated Jun 10, 2026
Open redirect in Jenkins 2.567 and earlier and LTS 2.555.2 and earlier allows remote attackers to redirect users to an attacker-controlled domain. The post-login flow for the Delegate to servlet container security realm accepts the from parameter as a redirect target without verifying that it is safe. The realm must be configured and a user must complete login through an attacker-supplied URL, enabling phishing without direct data access or service interruption.
Summary
What happened
Open redirect in Jenkins 2.567 and earlier and LTS 2.555.2 and earlier allows remote attackers to redirect users to an attacker-controlled domain. The post-login flow for the Delegate to servlet container security realm accepts the from parameter as a redirect target without verifying that it is safe. The realm must be configured and a user must complete login through an attacker-supplied URL, enabling phishing without direct data access or service interruption.
The record
- CVE
- CVE-2026-53440
- Published
- Jun 10, 2026
- Updated
- Jun 10, 2026
- Vendor
- Jenkins Project
- Product
- Jenkins
- Classifications
- CWE-601, T1566.002
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 10, 2026CVE publishedPublication date reported by the CVE source.
- Jun 10, 2026Record updatedLatest update available in the CVE record.
Exploitability
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What is affected?
Published CVSS scores
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Attacks
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Weakness, pattern, technique
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Technologies
Your stack
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Your stack
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