{"id":"UBUNTU-CVE-2026-5745","details":"A flaw was found in libarchive. A NULL pointer dereference vulnerability exists in the ACL parsing logic, specifically within the archive_acl_from_text_nl() function. When processing a malformed ACL string (such as a bare \"d\" or \"default\" tag without subsequent fields), the function fails to perform adequate validation before advancing the pointer. An attacker can exploit this by providing a maliciously crafted archive, causing an application utilizing the libarchive API (such as bsdtar) to crash, resulting in a Denial of Service (DoS).","modified":"2026-07-23T01:15:36.119094954Z","published":"2026-04-07T16:16:00Z","related":["USN-8581-1"],"upstream":["CVE-2026-5745"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-5745"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-5745"},{"type":"REPORT","url":"https://access.redhat.com/security/cve/CVE-2026-5745"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8581-1"}],"affected":[{"package":{"name":"libarchive","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/libarchive?arch=source&distro=esm-infra%2Ffocal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.4.0-2ubuntu1.5+esm3"}]}],"versions":["3.4.0-1","3.4.0-1build1","3.4.0-1ubuntu2","3.4.0-2ubuntu1","3.4.0-2ubuntu1.1","3.4.0-2ubuntu1.2","3.4.0-2ubuntu1.3","3.4.0-2ubuntu1.4","3.4.0-2ubuntu1.5","3.4.0-2ubuntu1.5+esm1","3.4.0-2ubuntu1.5+esm2"],"ecosystem_specific":{"availability":"Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro","binaries":[{"binary_name":"libarchive-tools","binary_version":"3.4.0-2ubuntu1.5+esm3"},{"binary_version":"3.4.0-2ubuntu1.5+esm3","binary_name":"libarchive13"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-5745.json"}},{"package":{"name":"libarchive","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/libarchive?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.6.0-1ubuntu1.8"}]}],"versions":["3.4.3-2","3.4.3-2build1","3.5.2-1","3.5.2-1ubuntu1","3.6.0-1ubuntu1","3.6.0-1ubuntu1.1","3.6.0-1ubuntu1.2","3.6.0-1ubuntu1.3","3.6.0-1ubuntu1.4","3.6.0-1ubuntu1.5","3.6.0-1ubuntu1.6","3.6.0-1ubuntu1.7"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_name":"libarchive-tools","binary_version":"3.6.0-1ubuntu1.8"},{"binary_version":"3.6.0-1ubuntu1.8","binary_name":"libarchive13"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-5745.json"}},{"package":{"name":"libarchive","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/libarchive?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.7.2-2ubuntu0.8"}]}],"versions":["3.6.2-1ubuntu1","3.7.2-1ubuntu1","3.7.2-1ubuntu2","3.7.2-1.1ubuntu2","3.7.2-2","3.7.2-2ubuntu0.1","3.7.2-2ubuntu0.2","3.7.2-2ubuntu0.3","3.7.2-2ubuntu0.4","3.7.2-2ubuntu0.5","3.7.2-2ubuntu0.6","3.7.2-2ubuntu0.7"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_name":"libarchive-tools","binary_version":"3.7.2-2ubuntu0.8"},{"binary_name":"libarchive13t64","binary_version":"3.7.2-2ubuntu0.8"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-5745.json"}},{"package":{"name":"libarchive","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/libarchive?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.7.7-0ubuntu2","3.7.7-0ubuntu2.1","3.7.7-0ubuntu2.2","3.7.7-0ubuntu3","3.7.7-0ubuntu3.1","3.7.7-0ubuntu3.2"],"ecosystem_specific":{"binaries":[{"binary_name":"libarchive-tools","binary_version":"3.7.7-0ubuntu3.2"},{"binary_version":"3.7.7-0ubuntu3.2","binary_name":"libarchive13t64"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-5745.json"}},{"package":{"name":"libarchive","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/libarchive?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.8.5-1ubuntu2.2"}]}],"versions":["3.7.7-0ubuntu3","3.8.5-1ubuntu1","3.8.5-1ubuntu2","3.8.5-1ubuntu2.1"],"ecosystem_specific":{"binaries":[{"binary_name":"libarchive-tools","binary_version":"3.8.5-1ubuntu2.2"},{"binary_name":"libarchive13t64","binary_version":"3.8.5-1ubuntu2.2"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-5745.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}]}