{"id":"UBUNTU-CVE-2021-30500","details":"Null pointer dereference was found in upx PackLinuxElf::canUnpack() in p_lx_elf.cpp,in version UPX 4.0.0. That allow attackers to execute arbitrary code and cause a denial of service via a crafted file.","modified":"2026-05-20T16:06:27.634335888Z","published":"2021-05-27T00:15:00Z","upstream":["CVE-2021-30500"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-30500"},{"type":"REPORT","url":"https://github.com/upx/upx/issues/485"},{"type":"REPORT","url":"https://github.com/upx/upx/commit/90279abdfcd235172eab99651043051188938dcc"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2021-30500"}],"affected":[{"package":{"name":"upx-ucl","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/upx-ucl?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.91-1"],"ecosystem_specific":{"binaries":[{"binary_name":"upx-ucl","binary_version":"3.91-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-30500.json"}},{"package":{"name":"upx-ucl","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/upx-ucl?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.94-2","3.94-3","3.94-4"],"ecosystem_specific":{"binaries":[{"binary_version":"3.94-4","binary_name":"upx-ucl"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-30500.json"}},{"package":{"name":"upx-ucl","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/upx-ucl?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.95-2","3.95-2build1"],"ecosystem_specific":{"binaries":[{"binary_name":"upx-ucl","binary_version":"3.95-2build1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-30500.json"}},{"package":{"name":"upx-ucl","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/upx-ucl?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.96-2","3.96-3"],"ecosystem_specific":{"binaries":[{"binary_name":"upx-ucl","binary_version":"3.96-3"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-30500.json"}},{"package":{"name":"upx-ucl","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/upx-ucl?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.96-3","4.2.2-3"],"ecosystem_specific":{"binaries":[{"binary_name":"upx-ucl","binary_version":"4.2.2-3"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-30500.json"}},{"package":{"name":"upx-ucl","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/upx-ucl?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.2.4-1","4.2.4-1.1"],"ecosystem_specific":{"binaries":[{"binary_name":"upx-ucl","binary_version":"4.2.4-1.1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-30500.json"}},{"package":{"name":"upx-ucl","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/upx-ucl?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.2.4-1.1","4.2.4-1.1build1"],"ecosystem_specific":{"binaries":[{"binary_version":"4.2.4-1.1build1","binary_name":"upx-ucl"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-30500.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:H/I:H/A:H"},{"type":"Ubuntu","score":"medium"}]}