{"id":"UBUNTU-CVE-2026-86219","details":"Authen::SASL::Perl::DIGEST_MD5 versions before 2.2100 for Perl accept replayed authentication responses via unverified nonce in server_step. server_start generates a fresh nonce and sends it in the challenge, and nothing later compares that value against the nonce the client returns. server_step derives the expected digest from the client's own parameters, so a response verifies whenever its digest matches the nonce it carries. The count table it also checks is keyed on the client-supplied nonce and starts empty in each new server object, so a captured first response, carrying `nc=00000001`, passes that too. RFC 2831 defines the nonce in the response as the value the server sent in the preceding challenge. An attacker who observes one successful `qop=auth` exchange can replay the captured response against a later session for the same service, host, realm and user, and authenticate as that user without knowing the password.","modified":"2026-09-16T14:03:45.581123566Z","published":"2026-09-06T18:17:00Z","upstream":["CVE-2026-86219"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-86219"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-86219"},{"type":"REPORT","url":"https://lists.security.metacpan.org/cve-announce/msg/43326063/"}],"affected":[{"package":{"name":"libauthen-sasl-perl","ecosystem":"Ubuntu:14.04:LTS","purl":"pkg:deb/ubuntu/libauthen-sasl-perl?arch=source&distro=trusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.1500-1"],"ecosystem_specific":{"binaries":[{"binary_name":"libauthen-sasl-perl","binary_version":"2.1500-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-86219.json"}},{"package":{"name":"libauthen-sasl-perl","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/libauthen-sasl-perl?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.1600-1"],"ecosystem_specific":{"binaries":[{"binary_name":"libauthen-sasl-perl","binary_version":"2.1600-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-86219.json"}},{"package":{"name":"libauthen-sasl-perl","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/libauthen-sasl-perl?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.1600-1"],"ecosystem_specific":{"binaries":[{"binary_name":"libauthen-sasl-perl","binary_version":"2.1600-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-86219.json"}},{"package":{"name":"libauthen-sasl-perl","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/libauthen-sasl-perl?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.1600-1"],"ecosystem_specific":{"binaries":[{"binary_name":"libauthen-sasl-perl","binary_version":"2.1600-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-86219.json"}},{"package":{"name":"libauthen-sasl-perl","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/libauthen-sasl-perl?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.1600-1.1"],"ecosystem_specific":{"binaries":[{"binary_name":"libauthen-sasl-perl","binary_version":"2.1600-1.1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-86219.json"}},{"package":{"name":"libauthen-sasl-perl","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/libauthen-sasl-perl?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.1600-3","2.1700-1"],"ecosystem_specific":{"binaries":[{"binary_name":"libauthen-sasl-perl","binary_version":"2.1700-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-86219.json"}},{"package":{"name":"libauthen-sasl-perl","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/libauthen-sasl-perl?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.1700-1","2.2000-1"],"ecosystem_specific":{"binaries":[{"binary_name":"libauthen-sasl-perl","binary_version":"2.2000-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-86219.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]}