{"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":"2026-05-21T18:11:56.879511425Z","published":"2026-04-07T16:16:00Z","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"}],"affected":[{"package":{"name":"libarchive","ecosystem":"Ubuntu:Pro:14.04:LTS","purl":"pkg:deb/ubuntu/libarchive?arch=source&distro=esm-infra-legacy%2Ftrusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.1.2-5ubuntu1","3.1.2-7ubuntu1","3.1.2-7ubuntu2","3.1.2-7ubuntu2.1","3.1.2-7ubuntu2.2","3.1.2-7ubuntu2.3","3.1.2-7ubuntu2.4","3.1.2-7ubuntu2.6","3.1.2-7ubuntu2.7","3.1.2-7ubuntu2.8","3.1.2-7ubuntu2.8+esm1","3.1.2-7ubuntu2.8+esm3","3.1.2-7ubuntu2.8+esm4","3.1.2-7ubuntu2.8+esm5"],"ecosystem_specific":{"binaries":[{"binary_version":"3.1.2-7ubuntu2.8+esm5","binary_name":"bsdcpio"},{"binary_version":"3.1.2-7ubuntu2.8+esm5","binary_name":"bsdtar"},{"binary_version":"3.1.2-7ubuntu2.8+esm5","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:Pro:16.04:LTS","purl":"pkg:deb/ubuntu/libarchive?arch=source&distro=esm-infra-legacy%2Fxenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.1.2-11build1","3.1.2-11ubuntu0.16.04.1","3.1.2-11ubuntu0.16.04.2","3.1.2-11ubuntu0.16.04.3","3.1.2-11ubuntu0.16.04.4","3.1.2-11ubuntu0.16.04.5","3.1.2-11ubuntu0.16.04.6","3.1.2-11ubuntu0.16.04.7","3.1.2-11ubuntu0.16.04.8","3.1.2-11ubuntu0.16.04.8+esm1","3.1.2-11ubuntu0.16.04.8+esm2","3.1.2-11ubuntu0.16.04.8+esm3"],"ecosystem_specific":{"binaries":[{"binary_version":"3.1.2-11ubuntu0.16.04.8+esm3","binary_name":"bsdcpio"},{"binary_version":"3.1.2-11ubuntu0.16.04.8+esm3","binary_name":"bsdtar"},{"binary_version":"3.1.2-11ubuntu0.16.04.8+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:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/libarchive?arch=source&distro=esm-infra%2Fbionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.2.2-3.1","3.2.2-3.1ubuntu0.1","3.2.2-3.1ubuntu0.2","3.2.2-3.1ubuntu0.3","3.2.2-3.1ubuntu0.4","3.2.2-3.1ubuntu0.5","3.2.2-3.1ubuntu0.6","3.2.2-3.1ubuntu0.7","3.2.2-3.1ubuntu0.7+esm1","3.2.2-3.1ubuntu0.7+esm2","3.2.2-3.1ubuntu0.7+esm3"],"ecosystem_specific":{"binaries":[{"binary_version":"3.2.2-3.1ubuntu0.7+esm3","binary_name":"bsdcpio"},{"binary_version":"3.2.2-3.1ubuntu0.7+esm3","binary_name":"bsdtar"},{"binary_version":"3.2.2-3.1ubuntu0.7+esm3","binary_name":"libarchive-tools"},{"binary_version":"3.2.2-3.1ubuntu0.7+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:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/libarchive?arch=source&distro=esm-infra%2Ffocal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"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":{"binaries":[{"binary_version":"3.4.0-2ubuntu1.5+esm2","binary_name":"libarchive-tools"},{"binary_version":"3.4.0-2ubuntu1.5+esm2","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"}]}],"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":{"binaries":[{"binary_version":"3.6.0-1ubuntu1.7","binary_name":"libarchive-tools"},{"binary_version":"3.6.0-1ubuntu1.7","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"}]}],"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":{"binaries":[{"binary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