{"id":"UBUNTU-CVE-2026-5089","details":"YAML::Syck versions before 1.38 for Perl  has an out-of-bounds read. The base60 (sexagesimal) parsing code in perl_syck.h has a buffer underflow bug in both int#base60 and float#base60 handlers. When processing the leftmost segment of a colon-separated value (e.g., the 1 in 1:30:45), the inner while loop can decrement a pointer past the start of the string buffer:     while ( colon \u003e= ptr && *colon != ':' )     {         colon--;     }     if ( *colon == ':' ) *colon = '\\0';  // colon may be ptr-1 here When no colon is found (final/leftmost segment), colon becomes ptr-1, and the subsequent *colon dereference reads one byte before the allocated buffer.","modified":"2026-05-20T22:03:09.574347137Z","published":"2026-05-12T17:16:00Z","upstream":["CVE-2026-5089"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-5089"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-5089"},{"type":"REPORT","url":"https://lists.security.metacpan.org/cve-announce/msg/39981051/"},{"type":"REPORT","url":"https://github.com/cpan-authors/YAML-Syck/issues/132"},{"type":"REPORT","url":"https://github.com/cpan-authors/YAML-Syck/pull/133"}],"affected":[{"package":{"name":"libyaml-syck-perl","ecosystem":"Ubuntu:Pro:16.04:LTS","purl":"pkg:deb/ubuntu/libyaml-syck-perl?arch=source&distro=esm-apps%2Fxenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.27-2build2","1.29-1","1.29-1build1","1.29-1ubuntu0.16.04.1~esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"libyaml-syck-perl","binary_version":"1.29-1ubuntu0.16.04.1~esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-5089.json"}},{"package":{"name":"libyaml-syck-perl","ecosystem":"Ubuntu:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/libyaml-syck-perl?arch=source&distro=esm-apps%2Fbionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.29-1build3","1.29-1ubuntu0.18.04.1~esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"libyaml-syck-perl","binary_version":"1.29-1ubuntu0.18.04.1~esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-5089.json"}},{"package":{"name":"libyaml-syck-perl","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/libyaml-syck-perl?arch=source&distro=esm-apps%2Ffocal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.31-1","1.31-1build1","1.31-1ubuntu0.1~esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"libyaml-syck-perl","binary_version":"1.31-1ubuntu0.1~esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-5089.json"}},{"package":{"name":"libyaml-syck-perl","ecosystem":"Ubuntu:Pro:22.04:LTS","purl":"pkg:deb/ubuntu/libyaml-syck-perl?arch=source&distro=esm-apps%2Fjammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.34-1build1","1.34-1build2","1.34-1ubuntu0.1~esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"libyaml-syck-perl","binary_version":"1.34-1ubuntu0.1~esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-5089.json"}},{"package":{"name":"libyaml-syck-perl","ecosystem":"Ubuntu:Pro:24.04:LTS","purl":"pkg:deb/ubuntu/libyaml-syck-perl?arch=source&distro=esm-apps%2Fnoble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.34-2","1.34-2build1","1.34-2build2","1.34-2build3","1.34-2ubuntu0.24.04.1~esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"libyaml-syck-perl","binary_version":"1.34-2ubuntu0.24.04.1~esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-5089.json"}},{"package":{"name":"libyaml-syck-perl","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/libyaml-syck-perl?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.34-2build4","1.34-3","1.34-3ubuntu0.1"],"ecosystem_specific":{"binaries":[{"binary_name":"libyaml-syck-perl","binary_version":"1.34-3ubuntu0.1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-5089.json"}},{"package":{"name":"libyaml-syck-perl","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/libyaml-syck-perl?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.34-3","1.34-4","1.36-1"],"ecosystem_specific":{"binaries":[{"binary_name":"libyaml-syck-perl","binary_version":"1.36-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-5089.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L"},{"type":"Ubuntu","score":"medium"}]}