{"id":"UBUNTU-CVE-2026-44896","details":"Mistune is a Python Markdown parser with renderers and plugins. In 3.2.0 and earlier, in src/mistune/directives/image.py, the render_figure() function concatenates figclass and figwidth options directly into HTML attributes without escaping. This allows attribute injection and XSS even when HTMLRenderer(escape=True) is used, because these values bypass the inline renderer. Version 3.2.1 contains a patch.","modified":"2026-06-12T09:12:11.114599610Z","published":"2026-05-26T21:16:00Z","upstream":["CVE-2026-44896"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-44896"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-44896"},{"type":"REPORT","url":"https://github.com/lepture/mistune/security/advisories/GHSA-58cw-g322-p94v"}],"affected":[{"package":{"name":"mistune","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/mistune?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.6-2","0.7.1-1"],"ecosystem_specific":{"binaries":[{"binary_name":"python-mistune","binary_version":"0.7.1-1"},{"binary_version":"0.7.1-1","binary_name":"python3-mistune"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-44896.json"}},{"package":{"name":"mistune","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/mistune?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.7.4-1","0.8-1","0.8.1-1","0.8.3-2"],"ecosystem_specific":{"binaries":[{"binary_version":"0.8.3-2","binary_name":"python-mistune"},{"binary_version":"0.8.3-2","binary_name":"python3-mistune"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-44896.json"}},{"package":{"name":"mistune","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/mistune?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.8.4-1","0.8.4-2"],"ecosystem_specific":{"binaries":[{"binary_version":"0.8.4-2","binary_name":"python3-mistune"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-44896.json"}},{"package":{"name":"mistune","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/mistune?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.8.4-4","0.8.4-5","2.0.0-1+really0.8.4-1"],"ecosystem_specific":{"binaries":[{"binary_name":"python3-mistune","binary_version":"2.0.0-1+really0.8.4-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-44896.json"}},{"package":{"name":"mistune0","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/mistune0?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.8.4-1","0.8.4-2"],"ecosystem_specific":{"binaries":[{"binary_version":"0.8.4-2","binary_name":"python3-mistune0"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-44896.json"}},{"package":{"name":"mistune","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/mistune?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.0.4-2","3.0.2-1"],"ecosystem_specific":{"binaries":[{"binary_version":"3.0.2-1","binary_name":"python3-mistune"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-44896.json"}},{"package":{"name":"mistune0","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/mistune0?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.8.4-2"],"ecosystem_specific":{"binaries":[{"binary_name":"python3-mistune0","binary_version":"0.8.4-2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-44896.json"}},{"package":{"name":"mistune","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/mistune?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.0.2-2","3.1.3-1"],"ecosystem_specific":{"binaries":[{"binary_name":"python3-mistune","binary_version":"3.1.3-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-44896.json"}},{"package":{"name":"mistune0","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/mistune0?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.8.4-4"],"ecosystem_specific":{"binaries":[{"binary_version":"0.8.4-4","binary_name":"python3-mistune0"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-44896.json"}},{"package":{"name":"mistune","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/mistune?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.1.3-1","3.1.4-1"],"ecosystem_specific":{"binaries":[{"binary_version":"3.1.4-1","binary_name":"python3-mistune"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU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