Bug 2464859 (CVE-2026-43860)

Summary: CVE-2026-43860 mutt: mutt: Authentication bypass due to IMAP CRAM-MD5 hash truncation
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: low Docs Contact:
Priority: low    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in mutt. During the IMAP CRAM-MD5 (Challenge-Response Authentication Mechanism - Message-Digest Algorithm 5) authentication, the password hash is truncated by one byte. This issue could allow a remote attacker to potentially bypass authentication, leading to unauthorized access.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Description OSIDB Bzimport 2026-05-04 07:01:35 UTC
mutt before 2.3.2 sometimes truncates the hash_passwd by one byte for IMAP auth_cram MD5 digest.