{"id":"UBUNTU-CVE-2021-33463","details":"An issue was discovered in yasm version 1.3.0. There is a NULL pointer dereference in yasm_expr__copy_except() in libyasm/expr.c.","modified":"2026-05-20T16:05:01.595127092Z","published":"2022-07-26T13:15:00Z","upstream":["CVE-2021-33463"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-33463"},{"type":"REPORT","url":"https://github.com/yasm/yasm/issues/174"},{"type":"REPORT","url":"https://gist.github.com/Clingto/bb632c0c463f4b2c97e4f65f751c5e6d"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2021-33463"}],"affected":[{"package":{"name":"yasm","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/yasm?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.3.0-2"],"ecosystem_specific":{"binaries":[{"binary_version":"1.3.0-2","binary_name":"yasm"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-33463.json"}},{"package":{"name":"yasm","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/yasm?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.3.0-2","1.3.0-2build1"],"ecosystem_specific":{"binaries":[{"binary_version":"1.3.0-2build1","binary_name":"yasm"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-33463.json"}},{"package":{"name":"yasm","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/yasm?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.3.0-2build1","1.3.0-2ubuntu1"],"ecosystem_specific":{"binaries":[{"binary_version":"1.3.0-2ubuntu1","binary_name":"yasm"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-33463.json"}},{"package":{"name":"yasm","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/yasm?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.3.0-2.1"],"ecosystem_specific":{"binaries":[{"binary_version":"1.3.0-2.1","binary_name":"yasm"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-33463.json"}},{"package":{"name":"yasm","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/yasm?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.3.0-4"],"ecosystem_specific":{"binaries":[{"binary_version":"1.3.0-4","binary_name":"yasm"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-33463.json"}},{"package":{"name":"yasm","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/yasm?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.3.0-5","1.3.0-7"],"ecosystem_specific":{"binaries":[{"binary_version":"1.3.0-7","binary_name":"yasm"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-33463.json"}},{"package":{"name":"yasm","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/yasm?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.3.0-7","1.3.0-8"],"ecosystem_specific":{"binaries":[{"binary_version":"1.3.0-8","binary_name":"yasm"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-33463.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"}]}