Bug 2461204 (CVE-2026-5545)

Summary: CVE-2026-5545 curl: libcurl: Authentication bypass due to incorrect HTTP Negotiate connection reuse
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerability-draftAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: adudiak, bbrownin, crizzo, csutherl, dbosanac, jclere, jmitchel, jreimann, kaycoth, kshier, mdessi, mrizzi, pbohmill, pcattana, pjindal, plodge, rhel-process-autobot, sdawley, security-response-team, stcannon, szappis, teagle, vchlup, watson-tool-maintainers, yguenane
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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Doc Text:
A flaw was found in libcurl. An application using libcurl that performs an authenticated HTTP(S) request after a Negotiate-authenticated one to the same host may incorrectly reuse the previous connection. This authentication bypass vulnerability allows the second request to be sent over a connection authenticated with different credentials, potentially leading to unauthorized access or information disclosure.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Deadline: 2026-04-29   

Description OSIDB Bzimport 2026-04-23 16:48:54 UTC
A flaw was found in libcurl. An application using libcurl that performs an authenticated HTTP(S) request after a Negotiate-authenticated one to the same host may incorrectly reuse the previous connection. This authentication bypass vulnerability allows the second request to be sent over a connection authenticated with different credentials, potentially leading to unauthorized access or information disclosure.