{"id":"UBUNTU-CVE-2026-40356","details":"In MIT Kerberos 5 (aka krb5) before 1.22.3, there is an integer underflow and resultant out-of-bounds read if an application calls gss_accept_sec_context() on a system with a NegoEx mechanism registered in /etc/gss/mech. An unauthenticated remote attacker can trigger this, possibly causing the process to terminate in parse_message.","modified":"2026-08-05T11:30:03.623770390Z","published":"2026-04-28T07:16:00Z","related":["USN-8585-1"],"upstream":["CVE-2026-40356"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-40356"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-40356"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8585-1"}],"affected":[{"package":{"name":"krb5","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/krb5?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.19.2-2ubuntu0.8"}]}],"versions":["1.18.3-6","1.18.3-7","1.19.2-0ubuntu1","1.19.2-1","1.19.2-2","1.19.2-2ubuntu0.1","1.19.2-2ubuntu0.2","1.19.2-2ubuntu0.3","1.19.2-2ubuntu0.4","1.19.2-2ubuntu0.5","1.19.2-2ubuntu0.6","1.19.2-2ubuntu0.7"],"ecosystem_specific":{"binaries":[{"binary_name":"krb5-admin-server","binary_version":"1.19.2-2ubuntu0.8"},{"binary_name":"krb5-gss-samples","binary_version":"1.19.2-2ubuntu0.8"},{"binary_version":"1.19.2-2ubuntu0.8","binary_name":"krb5-k5tls"},{"binary_name":"krb5-kdc","binary_version":"1.19.2-2ubuntu0.8"},{"binary_name":"krb5-kdc-ldap","binary_version":"1.19.2-2ubuntu0.8"},{"binary_name":"krb5-kpropd","binary_version":"1.19.2-2ubuntu0.8"},{"binary_name":"krb5-locales","binary_version":"1.19.2-2ubuntu0.8"},{"binary_name":"krb5-multidev","binary_version":"1.19.2-2ubuntu0.8"},{"binary_version":"1.19.2-2ubuntu0.8","binary_name":"krb5-otp"},{"binary_version":"1.19.2-2ubuntu0.8","binary_name":"krb5-pkinit"},{"binary_version":"1.19.2-2ubuntu0.8","binary_name":"krb5-user"},{"binary_name":"libgssapi-krb5-2","binary_version":"1.19.2-2ubuntu0.8"},{"binary_name":"libgssrpc4","binary_version":"1.19.2-2ubuntu0.8"},{"binary_version":"1.19.2-2ubuntu0.8","binary_name":"libk5crypto3"},{"binary_name":"libkadm5clnt-mit12","binary_version":"1.19.2-2ubuntu0.8"},{"binary_version":"1.19.2-2ubuntu0.8","binary_name":"libkadm5srv-mit12"},{"binary_name":"libkdb5-10","binary_version":"1.19.2-2ubuntu0.8"},{"binary_name":"libkrad0","binary_version":"1.19.2-2ubuntu0.8"},{"binary_version":"1.19.2-2ubuntu0.8","binary_name":"libkrb5-3"},{"binary_name":"libkrb5support0","binary_version":"1.19.2-2ubuntu0.8"}],"availability":"No 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