{"id":"UBUNTU-CVE-2021-40648","details":"In man2html 1.6g, a filename can be created to overwrite the previous size parameter of the next chunk and the fd, bk, fd_nextsize, bk_nextsize of the current chunk. The next chunk is then freed later on, causing a freeing of an arbitrary amount of memory.","modified":"2026-05-20T16:05:08.830685879Z","published":"2022-09-09T18:15:00Z","upstream":["CVE-2021-40648"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-40648"},{"type":"REPORT","url":"https://gist.github.com/untaman/cb58123fe89fc65e3984165db5d40933"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2021-40648"}],"affected":[{"package":{"name":"man2html","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/man2html?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.6g-7","1.6g-8"],"ecosystem_specific":{"binaries":[{"binary_name":"man2html","binary_version":"1.6g-8"},{"binary_name":"man2html-base","binary_version":"1.6g-8"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-40648.json"}},{"package":{"name":"man2html","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/man2html?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.6g-9","1.6g-9ubuntu1","1.6g-11"],"ecosystem_specific":{"binaries":[{"binary_name":"man2html","binary_version":"1.6g-11"},{"binary_name":"man2html-base","binary_version":"1.6g-11"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-40648.json"}},{"package":{"name":"man2html","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/man2html?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.6g-12"],"ecosystem_specific":{"binaries":[{"binary_name":"man2html","binary_version":"1.6g-12"},{"binary_version":"1.6g-12","binary_name":"man2html-base"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-40648.json"}},{"package":{"name":"man2html","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/man2html?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.6g-14"],"ecosystem_specific":{"binaries":[{"binary_version":"1.6g-14","binary_name":"man2html"},{"binary_name":"man2html-base","binary_version":"1.6g-14"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-40648.json"}},{"package":{"name":"man2html","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/man2html?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.6g-14","1.6g-15","1.6g-16"],"ecosystem_specific":{"binaries":[{"binary_version":"1.6g-16","binary_name":"man2html"},{"binary_name":"man2html-base","binary_version":"1.6g-16"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-40648.json"}},{"package":{"name":"man2html","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/man2html?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.6g-16"],"ecosystem_specific":{"binaries":[{"binary_version":"1.6g-16","binary_name":"man2html"},{"binary_name":"man2html-base","binary_version":"1.6g-16"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-40648.json"}},{"package":{"name":"man2html","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/man2html?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.6g-16","1.6g-16build1"],"ecosystem_specific":{"binaries":[{"binary_name":"man2html","binary_version":"1.6g-16build1"},{"binary_version":"1.6g-16build1","binary_name":"man2html-base"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-40648.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"}]}