{"id":"CVE-2026-115351","aliases":["DEBIAN-CVE-2026-115351","EUVD-2026-108420","GHSA-2jmw-jfgq-rw98","GHSA-xmwc-wjpr-q378","UBUNTU-CVE-2026-115351"],"status":"published","title":"Mistune 3.2.1 before 3.3.0 CSS Injection via Figure Directive figwidth Option","description":"Mistune from 3.2.1 before 3.3.0 contains a CSS injection vulnerability that allows attackers controlling markdown input to inject arbitrary style declarations via the unvalidated figwidth option of the figure directive. Attackers can append declarations like background:url() to the rendered figure style attribute, forcing victim browsers to send requests to attacker servers and leak attribute values.","severity":{"version":"4.0","score":5.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00221,"percentile":0.12821,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-94"],"published":"2026-10-22T19:13:27Z","modified":"2026-10-31T02:30:22Z","affected":[{"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":"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-xmwc-wjpr-q378","tags":["vendor-advisory","exploit","advisory","report"]},{"url":"https://www.vulncheck.com/advisories/mistune-3.2.1-before-3.3.0-css-injection-via-figure-directive-figwidth-option","tags":["third-party-advisory","advisory","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-115351","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-2jmw-jfgq-rw98"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/115xxx/CVE-2026-115351.json","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-115351","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2026-115351","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-115351","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2026-115351","title":"Mistune 3.2.1 before 3.3.0 CSS Injection via Figure Directive figwidth Option","description":"Mistune from 3.2.1 before 3.3.0 contains a CSS injection vulnerability that allows attackers controlling markdown input to inject arbitrary style declarations via the unvalidated figwidth option of the figure directive. Attackers can append declarations like background:url() to the rendered figure style attribute, forcing victim browsers to send requests to attacker servers and leak attribute values.","status":"published","published":"2026-10-22T19:13:27.678Z","modified":"2026-10-29T11:53:14.49Z","cvss":[{"version":"4.0","score":5.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N","level":"medium","assessor":"cna"},{"version":"3.1","score":4.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-94"],"updated_at":"2026-11-02T14:20:01.618694Z"}],"euvd":[{"id":"EUVD-2026-108420","description":"Mistune from 3.2.1 before 3.3.0 contains a CSS injection vulnerability that allows attackers controlling markdown input to inject arbitrary style declarations via the unvalidated figwidth option of the figure directive. Attackers can append declarations like background:url() to the rendered figure style attribute, forcing victim browsers to send requests to attacker servers and leak attribute values.","status":"published","published":"2026-10-22T19:13:27Z","modified":"2026-10-29T11:53:14Z","cvss":[{"version":"4.0","score":5.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N","level":"medium"}],"updated_at":"2026-11-02T16:59:17.279653Z"}],"ghsa":[{"id":"GHSA-2jmw-jfgq-rw98","title":"Mistune from 3.2.1 before 3.3.0 contains a CSS injection vulnerability that allows attackers...","description":"Mistune from 3.2.1 before 3.3.0 contains a CSS injection vulnerability that allows attackers controlling markdown input to inject arbitrary style declarations via the unvalidated figwidth option of the figure directive. Attackers can append declarations like background:url() to the rendered figure style attribute, forcing victim browsers to send requests to attacker servers and leak attribute values.","status":"published","published":"2026-10-22T21:32:36Z","modified":"2026-10-22T21:32:36Z","cvss":[{"version":"4.0","score":5.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/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":"medium"},{"version":"3.1","score":4.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N","level":"medium"}],"cwes":["CWE-94"],"updated_at":"2026-11-02T15:14:17.600276Z"}],"nvd":[{"id":"CVE-2026-115351","description":"Mistune from 3.2.1 before 3.3.0 contains a CSS injection vulnerability that allows attackers controlling markdown input to inject arbitrary style declarations via the unvalidated figwidth option of the figure directive. Attackers can append declarations like background:url() to the rendered figure style attribute, forcing victim browsers to send requests to attacker servers and leak attribute values.","status":"published","published":"2026-10-22T19:17:40.92Z","modified":"2026-10-29T12:17:10.937Z","cvss":[{"version":"4.0","score":5.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/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":"medium","assessor":"secondary"},{"version":"3.1","score":4.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-94"],"updated_at":"2026-11-02T14:13:02.724605Z"}],"osv":[{"id":"CVE-2026-115351","title":"Mistune 3.2.1 before 3.3.0 CSS Injection via Figure Directive figwidth Option","description":"Mistune from 3.2.1 before 3.3.0 contains a CSS injection vulnerability that allows attackers controlling markdown input to inject arbitrary style declarations via the unvalidated figwidth option of the figure directive. Attackers can append declarations like background:url() to the rendered figure style attribute, forcing victim browsers to send requests to attacker servers and leak attribute values.","status":"published","published":"2026-10-22T19:13:27.678Z","modified":"2026-10-31T02:30:22.8265806Z","cvss":[{"version":"4.0","score":5.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N","level":"medium"}],"cwes":["CWE-94"],"updated_at":"2026-11-02T15:44:56.675758Z"},{"id":"DEBIAN-CVE-2026-115351","description":"Mistune from 3.2.1 before 3.3.0 contains a CSS injection vulnerability that allows attackers controlling markdown input to inject arbitrary style declarations via the unvalidated figwidth option of the figure directive. Attackers can append declarations like background:url() to the rendered figure style attribute, forcing victim browsers to send requests to attacker servers and leak attribute values.","status":"published","published":"2026-10-22T19:17:40.92Z","modified":"2026-10-30T10:00:15.530022972Z","cvss":[{"version":"4.0","score":5.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/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":"medium"}],"updated_at":"2026-11-02T15:45:50.923612Z"},{"id":"UBUNTU-CVE-2026-115351","description":"Mistune from 3.2.1 before 3.3.0 contains a CSS injection vulnerability that allows attackers controlling markdown input to inject arbitrary style declarations via the unvalidated figwidth option of the figure directive. Attackers can append declarations like background:url() to the rendered figure style attribute, forcing victim browsers to send requests to attacker servers and leak attribute values.","status":"published","published":"2026-10-22T19:17:00Z","modified":"2026-10-28T17:50:37Z","cvss":[{"version":"3.1","score":4.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N","level":"medium"},{"version":"4.0","score":5.3,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N","level":"medium"}],"updated_at":"2026-11-02T16:55:59.591851Z"}]}}