Bug 2487544 (CVE-2026-53437)

Summary: CVE-2026-53437 jenkins: Jenkins: Phishing attack via improper redirect URL validation
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Jenkins. This vulnerability allows a remote attacker to perform phishing attacks by crafting a malicious redirect URL. The flaw occurs because Jenkins improperly validates redirect URLs after login, specifically when tab or newline characters are present between the `//` in the URL. This can trick users into visiting malicious sites, potentially leading to credential theft or other security compromises.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-06-10 14:02:11 UTC 
Jenkins 2.567 and earlier, LTS 2.555.2 and earlier improperly determines that a redirect URL after login is legitimately pointing to Jenkins when it contains tab or newline characters between `//`, allowing attackers to perform phishing attacks.