{"id":"USN-4635-1","summary":"krb5 vulnerability","details":"Demi Obenour discovered that Kerberos incorrectly handled certain ASN.1.\nAn attacker could possibly use this issue to cause a denial of service.\n","modified":"2026-02-10T04:41:59Z","published":"2020-11-17T13:35:56Z","related":["UBUNTU-CVE-2020-28196"],"upstream":["CVE-2020-28196","UBUNTU-CVE-2020-28196"],"references":[{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-4635-1"},{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2020-28196"}],"affected":[{"package":{"name":"krb5","ecosystem":"Ubuntu:Pro:14.04:LTS","purl":"pkg:deb/ubuntu/krb5@1.12+dfsg-2ubuntu5.4+esm2?arch=source&distro=trusty/esm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.12+dfsg-2ubuntu5.4+esm2"}]}],"versions":["1.10.1+dfsg-6.1ubuntu1","1.11.3+dfsg-3ubuntu2","1.12+dfsg-2ubuntu1","1.12+dfsg-2ubuntu2","1.12+dfsg-2ubuntu3","1.12+dfsg-2ubuntu4","1.12+dfsg-2ubuntu4.2","1.12+dfsg-2ubuntu5","1.12+dfsg-2ubuntu5.1","1.12+dfsg-2ubuntu5.2","1.12+dfsg-2ubuntu5.3","1.12+dfsg-2ubuntu5.4","1.12+dfsg-2ubuntu5.4+esm1"],"ecosystem_specific":{"availability":"Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro","binaries":[{"binary_name":"krb5-admin-server","binary_version":"1.12+dfsg-2ubuntu5.4+esm2"},{"binary_name":"krb5-gss-samples","binary_version":"1.12+dfsg-2ubuntu5.4+esm2"},{"binary_name":"krb5-kdc","binary_version":"1.12+dfsg-2ubuntu5.4+esm2"},{"binary_name":"krb5-kdc-ldap","binary_version":"1.12+dfsg-2ubuntu5.4+esm2"},{"binary_name":"krb5-locales","binary_version":"1.12+dfsg-2ubuntu5.4+esm2"},{"binary_name":"krb5-multidev","binary_version":"1.12+dfsg-2ubuntu5.4+esm2"},{"binary_name":"krb5-otp","binary_version":"1.12+dfsg-2ubuntu5.4+esm2"},{"binary_name":"krb5-pkinit","binary_version":"1.12+dfsg-2ubuntu5.4+esm2"},{"binary_name":"krb5-user","binary_version":"1.12+dfsg-2ubuntu5.4+esm2"},{"binary_name":"libgssapi-krb5-2","binary_version":"1.12+dfsg-2ubuntu5.4+esm2"},{"binary_name":"libgssrpc4","binary_version":"1.12+dfsg-2ubuntu5.4+esm2"},{"binary_name":"libk5crypto3","binary_version":"1.12+dfsg-2ubuntu5.4+esm2"},{"binary_name":"libkadm5clnt-mit9","binary_version":"1.12+dfsg-2ubuntu5.4+esm2"},{"binary_name":"libkadm5srv-mit8","binary_version":"1.12+dfsg-2ubuntu5.4+esm2"},{"binary_name":"libkadm5srv-mit9","binary_version":"1.12+dfsg-2ubuntu5.4+esm2"},{"binary_name":"libkdb5-7","binary_version":"1.12+dfsg-2ubuntu5.4+esm2"},{"binary_name":"libkrad-dev","binary_version":"1.12+dfsg-2ubuntu5.4+esm2"},{"binary_name":"libkrad0","binary_version":"1.12+dfsg-2ubuntu5.4+esm2"},{"binary_name":"libkrb5-3","binary_version":"1.12+dfsg-2ubuntu5.4+esm2"},{"binary_name":"libkrb5-dev","binary_version":"1.12+dfsg-2ubuntu5.4+esm2"},{"binary_name":"libkrb5support0","binary_version":"1.12+dfsg-2ubuntu5.4+esm2"}]},"database_specific":{"cves_map":{"ecosystem":"Ubuntu:Pro:14.04:LTS","cves":[{"severity":[{"score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","type":"CVSS_V3"},{"score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","type":"CVSS_V3"},{"score":"medium","type":"Ubuntu"}],"id":"CVE-2020-28196"}]},"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/usn/USN-4635-1.json"}},{"package":{"name":"krb5","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/krb5@1.13.2+dfsg-5ubuntu2.2?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.13.2+dfsg-5ubuntu2.2"}]}],"versions":["1.13.2+dfsg-2","1.13.2+dfsg-3","1.13.2+dfsg-4","1.13.2+dfsg-5","1.13.2+dfsg-5ubuntu1","1.13.2+dfsg-5ubuntu2","1.13.2+dfsg-5ubuntu2.1"],"ecosystem_specific":{"availability":"No 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