{"id":"CVE-2026-115355","aliases":["DEBIAN-CVE-2026-115355","EUVD-2026-108425","GHSA-8cqv-vvq2-6p8c","GHSA-h7ww-273w-6cm8","OESA-2026-4791","OESA-2026-4793","OESA-2026-4794","UBUNTU-CVE-2026-115355"],"status":"published","title":"Mistune before 3.3.0 Path Traversal and XSS via Include Directive","description":"Mistune before 3.3.0 contains a path traversal vulnerability in the Include directive that allows attackers to read arbitrary files by supplying ../ sequences in include paths. Attackers can also inject HTML through unescaped error messages and included file contents to perform cross-site scripting even when escape=True is set.","severity":{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00461,"percentile":0.40377,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-22"],"published":"2026-10-22T19:13:31Z","modified":"2026-11-11T12:45:06Z","fixes":[{"ecosystem":"PyPI","package":"mistune","fixed_in":["3.3.0"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"PyPI","package":"mistune","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"3.2.0"},{"fixed":"3.3.0"}]}]},{"source":"osv","ecosystem":"Debian:12","package":"mistune","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.0.4-1","2.0.4-2","3.0.2-1","3.0.2-2","3.1.3-1","3.1.4-1","3.3.4-1","3.4.0-1"]},{"source":"osv","ecosystem":"Debian:13","package":"mistune","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.1.3-1","3.1.4-1","3.3.4-1","3.4.0-1"]},{"source":"osv","ecosystem":"Debian:14","package":"mistune","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.1.3-1","3.1.4-1","3.3.4-1","3.4.0-1"]},{"source":"osv","ecosystem":"PyPI","package":"mistune","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.3.0"}]}],"versions":["0.1.0","0.2.0","0.3.0","0.3.1","0.4","0.4.1","0.5","0.5.1","0.6","0.7","0.7.1","0.7.2","0.7.3","0.7.4","0.8","0.8.1","0.8.2","0.8.3","0.8.4","2.0.0","2.0.0a1","2.0.0a2","2.0.0a3","2.0.0a4","2.0.0a5","2.0.0a6","2.0.0rc1","2.0.1","2.0.2","2.0.3","2.0.4","2.0.5","2.1.0","3.0.0","3.0.0a1","3.0.0a2","3.0.0a3","3.0.0rc1","3.0.0rc2","3.0.0rc3","3.0.0rc4","3.0.0rc5","3.0.1","3.0.2","3.1.0","3.1.1","3.1.2","3.1.3","3.1.4","3.2.0","3.2.1"]},{"source":"osv","ecosystem":"openEuler:24.03-LTS-SP4","package":"python-mistune","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.0.4-4.oe2403sp4"}]}],"bundled":4},{"source":"osv","ecosystem":"openEuler:24.03-LTS-SP1","package":"python-mistune","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.0.4-4.oe2403sp1"}]}],"bundled":4},{"source":"osv","ecosystem":"openEuler:24.03-LTS-SP3","package":"python-mistune","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.0.4-4.oe2403sp3"}]}],"bundled":4},{"source":"osv","ecosystem":"Ubuntu:16.04:LTS","package":"mistune","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.6-2","0.7.1-1"]},{"source":"osv","ecosystem":"Ubuntu:18.04:LTS","package":"mistune","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.7.4-1","0.8-1","0.8.1-1","0.8.3-2"]},{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"mistune","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.8.4-1","0.8.4-2"]},{"source":"osv","ecosystem":"Ubuntu:22.04:LTS","package":"mistune","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.8.4-4","0.8.4-5","2.0.0-1+really0.8.4-1"]},{"source":"osv","ecosystem":"Ubuntu:24.04:LTS","package":"mistune","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.0.4-2","3.0.2-1"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"mistune","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.1.4-1"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"mistune","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.1.3-1","3.1.4-1"]}],"products":[{"vendor":"lepture","product":"mistune"}],"references":[{"url":"https://github.com/lepture/mistune/security/advisories/GHSA-h7ww-273w-6cm8","tags":["vendor-advisory","advisory","web","report"]},{"url":"https://www.vulncheck.com/advisories/mistune-before-3.3.0-path-traversal-and-xss-via-include-directive","tags":["third-party-advisory","advisory","web","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-115355","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-8cqv-vvq2-6p8c"},{"url":"https://github.com/lepture/mistune/commit/1bef343ade163fc3bb95572b15be720084cdb993","tags":["web"]},{"url":"https://github.com/lepture/mistune/releases/tag/v3.3.0","tags":["web"]},{"url":"https://github.com/advisories/GHSA-h7ww-273w-6cm8"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/115xxx/CVE-2026-115355.json","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-115355","tags":["advisory"]},{"url":"https://github.com/lepture/mistune","tags":["package"]},{"url":"https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-4791","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-115350","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-115353","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-115354","tags":["advisory"]},{"url":"https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-4793","tags":["advisory"]},{"url":"https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-4794","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2026-115355","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-115355","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2026-115355","title":"Mistune before 3.3.0 Path Traversal and XSS via Include Directive","description":"Mistune before 3.3.0 contains a path traversal vulnerability in the Include directive that allows attackers to read arbitrary files by supplying ../ sequences in include paths. Attackers can also inject HTML through unescaped error messages and included file contents to perform cross-site scripting even when escape=True is set.","status":"published","published":"2026-10-22T19:13:31.904Z","modified":"2026-10-29T13:48:43.278Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N","level":"high","assessor":"cna"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high","assessor":"cna"}],"cwes":["CWE-22"],"updated_at":"2026-11-02T14:20:01.618694Z"}],"euvd":[{"id":"EUVD-2026-108425","description":"Mistune before 3.3.0 contains a path traversal vulnerability in the Include directive that allows attackers to read arbitrary files by supplying ../ sequences in include paths. Attackers can also inject HTML through unescaped error messages and included file contents to perform cross-site scripting even when escape=True is set.","status":"published","published":"2026-10-22T19:13:31Z","modified":"2026-10-29T13:48:43Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N","level":"high"}],"updated_at":"2026-11-02T16:59:16.484344Z"}],"ghsa":[{"id":"GHSA-8cqv-vvq2-6p8c","title":"Duplicate Advisory: Mistune: Path Traversal and XSS in Include directive","description":"## Duplicate Advisory\n\nThis advisory has been withdrawn because it is a duplicate of GHSA-h7ww-273w-6cm8. This link is maintained to preserve external references.\n\n## Original Description\nMistune before 3.3.0 contains a path traversal vulnerability in the Include directive that allows attackers to read arbitrary files by supplying ../ sequences in include paths. Attackers can also inject HTML through unescaped error messages and included file contents to perform cross-site scripting even when escape=True is set.","status":"withdrawn","published":"2026-10-22T21:32:36Z","modified":"2026-10-23T20:46:29Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"},{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high"}],"cwes":["CWE-22"],"updated_at":"2026-11-02T14:41:35.723785Z"},{"id":"GHSA-h7ww-273w-6cm8","title":"Mistune: Path Traversal and XSS in Include directive","description":"The Include directive in `src/mistune/directives/include.py` does not validate that the resolved file path stays within the source directory, allowing path traversal via `../` sequences to read arbitrary files.\n\nAdditionally, error messages and included file contents are rendered without HTML escaping, leading to XSS even when `escape=True`.\n\nAffected functions:\n- Path resolution (lines 27-31)\n- `block_error()` in html.py (line 140)\n- `render_html_include()` (line 72)\n\nThe Include plugin must be explicitly enabled via the plugins parameter.","status":"published","published":"2026-10-23T20:46:47Z","modified":"2026-10-23T20:46:48Z","cwes":["CWE-22"],"updated_at":"2026-11-02T14:41:35.723785Z"}],"nvd":[{"id":"CVE-2026-115355","description":"Mistune before 3.3.0 contains a path traversal vulnerability in the Include directive that allows attackers to read arbitrary files by supplying ../ sequences in include paths. Attackers can also inject HTML through unescaped error messages and included file contents to perform cross-site scripting even when escape=True is set.","status":"published","published":"2026-10-22T19:17:41.52Z","modified":"2026-10-29T14:17:48.34Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high","assessor":"secondary"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high","assessor":"secondary"}],"cwes":["CWE-22"],"updated_at":"2026-11-02T14:13:02.724605Z"}],"osv":[{"id":"CVE-2026-115355","title":"Mistune before 3.3.0 Path Traversal and XSS via Include Directive","description":"Mistune before 3.3.0 contains a path traversal vulnerability in the Include directive that allows attackers to read arbitrary files by supplying ../ sequences in include paths. Attackers can also inject HTML through unescaped error messages and included file contents to perform cross-site scripting even when escape=True is set.","status":"published","published":"2026-10-22T19:13:31.904Z","modified":"2026-10-31T02:31:07.105942227Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N","level":"high"}],"cwes":["CWE-22"],"updated_at":"2026-11-02T15:44:56.675758Z"},{"id":"DEBIAN-CVE-2026-115355","description":"Mistune before 3.3.0 contains a path traversal vulnerability in the Include directive that allows attackers to read arbitrary files by supplying ../ sequences in include paths. Attackers can also inject HTML through unescaped error messages and included file contents to perform cross-site scripting even when escape=True is set.","status":"published","published":"2026-10-22T19:17:41.52Z","modified":"2026-10-30T10:00:16.179572285Z","cvss":[{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high"}],"updated_at":"2026-11-02T15:45:50.923612Z"},{"id":"GHSA-8cqv-vvq2-6p8c","title":"Duplicate Advisory: Mistune: Path Traversal and XSS in Include directive","description":"## Duplicate Advisory\n\nThis advisory has been withdrawn because it is a duplicate of GHSA-h7ww-273w-6cm8. This link is maintained to preserve external references.\n\n## Original Description\nMistune before 3.3.0 contains a path traversal vulnerability in the Include directive that allows attackers to read arbitrary files by supplying ../ sequences in include paths. Attackers can also inject HTML through unescaped error messages and included file contents to perform cross-site scripting even when escape=True is set.","status":"withdrawn","published":"2026-10-22T21:32:36Z","modified":"2026-10-23T21:00:04.307837522Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"},{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high"}],"cwes":["CWE-22"],"updated_at":"2026-11-02T15:46:42.077781Z"},{"id":"OESA-2026-4791","title":"python-mistune security update","description":"The python-mistune package is a fast yet powerful Python Markdown parser with renderers and plugins, compatible with sane CommonMark rules.\r\n\r\nSecurity Fix(es):\n\nMistune before 3.3.0 contains a cross-site scripting vulnerability in the Include directive that emits included .html, .xhtml, or .htm file content as raw block_html tokens. Attackers who can plant an HTML file readable by the renderer can reference it via an include directive, combined with path traversal, to execute stored scripts when escape=False is set.(CVE-2026-115350)\n\nMistune before 3.3.0 contains a path traversal vulnerability in the RST include directive that allows attackers to read arbitrary files by supplying relative or absolute paths. Attackers can submit markdown containing include directives referencing ../ sequences or absolute paths to embed sensitive files like credentials or environment data in rendered HTML.(CVE-2026-115353)\n\nMistune before 3.3.0 contains a path traversal vulnerability in the opt-in Include directive that allows attackers to read local files by supplying relative or absolute include paths. Attackers who submit Markdown rendered via Markdown.read() can disclose files such as /etc/passwd and inject unescaped HTML or script content into rendered output.(CVE-2026-115354)\n\nMistune before 3.3.0 contains a path traversal vulnerability in the Include directive that allows attackers to read arbitrary files by supplying ../ sequences in include paths. Attackers can also inject HTML through unescaped error messages and included file contents to perform cross-site scripting even when escape=True is set.(CVE-2026-115355)","status":"published","published":"2026-11-11T12:26:11Z","modified":"2026-11-11T12:45:06.801008324Z","cvss":[{"version":"3.1","score":8.6,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-11T13:08:46.301371Z"},{"id":"OESA-2026-4793","title":"python-mistune security update","description":"The python-mistune package is a fast yet powerful Python Markdown parser with renderers and plugins, compatible with sane CommonMark rules.\r\n\r\nSecurity Fix(es):\n\nMistune before 3.3.0 contains a cross-site scripting vulnerability in the Include directive that emits included .html, .xhtml, or .htm file content as raw block_html tokens. Attackers who can plant an HTML file readable by the renderer can reference it via an include directive, combined with path traversal, to execute stored scripts when escape=False is set.(CVE-2026-115350)\n\nMistune before 3.3.0 contains a path traversal vulnerability in the RST include directive that allows attackers to read arbitrary files by supplying relative or absolute paths. Attackers can submit markdown containing include directives referencing ../ sequences or absolute paths to embed sensitive files like credentials or environment data in rendered HTML.(CVE-2026-115353)\n\nMistune before 3.3.0 contains a path traversal vulnerability in the opt-in Include directive that allows attackers to read local files by supplying relative or absolute include paths. Attackers who submit Markdown rendered via Markdown.read() can disclose files such as /etc/passwd and inject unescaped HTML or script content into rendered output.(CVE-2026-115354)\n\nMistune before 3.3.0 contains a path traversal vulnerability in the Include directive that allows attackers to read arbitrary files by supplying ../ sequences in include paths. Attackers can also inject HTML through unescaped error messages and included file contents to perform cross-site scripting even when escape=True is set.(CVE-2026-115355)","status":"published","published":"2026-11-11T12:26:13Z","modified":"2026-11-11T12:45:06.998022896Z","cvss":[{"version":"3.1","score":8.6,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-11T13:08:46.301371Z"},{"id":"OESA-2026-4794","title":"python-mistune security update","description":"The python-mistune package is a fast yet powerful Python Markdown parser with renderers and plugins, compatible with sane CommonMark rules.\r\n\r\nSecurity Fix(es):\n\nMistune before 3.3.0 contains a cross-site scripting vulnerability in the Include directive that emits included .html, .xhtml, or .htm file content as raw block_html tokens. Attackers who can plant an HTML file readable by the renderer can reference it via an include directive, combined with path traversal, to execute stored scripts when escape=False is set.(CVE-2026-115350)\n\nMistune before 3.3.0 contains a path traversal vulnerability in the RST include directive that allows attackers to read arbitrary files by supplying relative or absolute paths. Attackers can submit markdown containing include directives referencing ../ sequences or absolute paths to embed sensitive files like credentials or environment data in rendered HTML.(CVE-2026-115353)\n\nMistune before 3.3.0 contains a path traversal vulnerability in the opt-in Include directive that allows attackers to read local files by supplying relative or absolute include paths. Attackers who submit Markdown rendered via Markdown.read() can disclose files such as /etc/passwd and inject unescaped HTML or script content into rendered output.(CVE-2026-115354)\n\nMistune before 3.3.0 contains a path traversal vulnerability in the Include directive that allows attackers to read arbitrary files by supplying ../ sequences in include paths. Attackers can also inject HTML through unescaped error messages and included file contents to perform cross-site scripting even when escape=True is set.(CVE-2026-115355)","status":"published","published":"2026-11-11T12:26:14Z","modified":"2026-11-11T12:45:06.796298601Z","cvss":[{"version":"3.1","score":8.6,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-11T13:08:46.301371Z"},{"id":"UBUNTU-CVE-2026-115355","description":"Mistune before 3.3.0 contains a path traversal vulnerability in the Include directive that allows attackers to read arbitrary files by supplying ../ sequences in include paths. Attackers can also inject HTML through unescaped error messages and included file contents to perform cross-site scripting even when escape=True is set.","status":"published","published":"2026-10-22T19:17:00Z","modified":"2026-10-28T17:50:37Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"},{"version":"4.0","score":8.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N","level":"high"}],"updated_at":"2026-11-02T16:55:59.591851Z"},{"id":"GHSA-h7ww-273w-6cm8","title":"Mistune: Path Traversal and XSS in Include directive","description":"The Include directive in `src/mistune/directives/include.py` does not validate that the resolved file path stays within the source directory, allowing path traversal via `../` sequences to read arbitrary files.\n\nAdditionally, error messages and included file contents are rendered without HTML escaping, leading to XSS even when `escape=True`.\n\nAffected functions:\n- Path resolution (lines 27-31)\n- `block_error()` in html.py (line 140)\n- `render_html_include()` (line 72)\n\nThe Include plugin must be explicitly enabled via the plugins parameter.","status":"published","published":"2026-10-23T20:46:47Z","modified":"2026-10-23T21:00:06.308204078Z","cwes":["CWE-22"],"updated_at":"2026-11-02T15:46:48.920784Z"}]}}