Bug 2548269 (CVE-2026-107778)

Summary: CVE-2026-107778 krb5: krb5: Denial of Service via crafted forwarded credentials
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: abokovoy, akhatavk, aos-team-art-private, asdas, dpaolell, eglynn, jdelft, jjoyce, jpretori, jrische, jschluet, jupierce, kbempah, lgarciaa, lhh, mbiarnes, mburns, mgarciac, ppalepu, ppostler, prdhamdh, rhel-process-autobot, sghai, sidsharm, solenoci, suppawar, vlaad, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in krb5. An authenticated remote attacker can cause a Denial of Service (DoS) by sending specially crafted forwarded credentials containing mismatched credential entries. This improper handling triggers a null pointer dereference, causing the service to crash and become unavailable.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-10-08 20:32:25 UTC
MIT Kerberos 5 (krb5) through 1.22.2 contains a NULL pointer dereference in make_cred_list() in rd_cred.c that allows authenticated Kerberos clients to crash services by sending mismatched KRB-CRED arrays. Attackers can send forwarded credentials with more tickets than ticket_info entries through gss_accept_sec_context() to crash GSS-API acceptor services, causing denial of service.