{"answers":{"affected":"4 open source packages ship an affected version, including mermaid. It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-41159 in the wild and no public exploit code.","fix":"Upgrade mermaid to a fixed version for your release line: 10.9.6 or 11.15.0.","what":"CVE-2026-41159 is a medium-severity cross-site scripting vulnerability in mermaid-js mermaid, published on 29 May 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link."},"fix_prompt":"Check this codebase for CVE-2026-41159 and fix it if it is affected.\n\nWhat it is: CVE-2026-41159 is a medium-severity cross-site scripting vulnerability in mermaid-js mermaid, published on 29 May 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.\nExploitation: There is no known exploitation of CVE-2026-41159 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- mermaid (npm): affected all versions; fixed in 10.9.6\n- mermaid (npm): affected all versions; fixed in 10.9.6\n- mermaid (npm): affected from 11.0.0-alpha.1; fixed in 11.15.0\n- mermaid (npm): affected from 11.0.0-alpha.1; fixed in 11.15.0\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-41159/ (Markdown: https://insights.sbomify.com/CVE-2026-41159/index.md)","id":"CVE-2026-41159","markdown":"https://insights.sbomify.com/CVE-2026-41159/index.md","name":"CVE-2026-41159","record":{"aliases":["DEBIAN-CVE-2026-41159","GHSA-87f9-hvmw-gh4p","MINI-686p-c639-hg28","MINI-hpvg-h3xp-x3jg","UBUNTU-CVE-2026-41159"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["data_read","other"],"network_reachable":"yes","non_default_config":false,"product_category":"JavaScript diagramming library","requires_auth":"none","summary":"Attackers can inject CSS to deface pages and exfiltrate DOM attributes via Mermaid configuration options, affecting applications using the library.","user_interaction":"required","vuln_class":"xss"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"mermaid","vendor":"mermaid_project"}],"cvss":{"score":5.3,"severity":"medium","source":"cna","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:L/SI:L/SA:L","version":"4.0"},"cwes":[{"id":"CWE-94","name":"Improper Control of Generation of Code"}],"description":"Mermaid is a JavaScript tool that uses Markdown-inspired text to create and modify diagrams and charts. Prior to 10.9.6 and 11.15.0,  Mermaid's default configuration allows injecting CSS that applies outside of the Mermaid diagram via the fontFamily, themeCSS, and altFontFamily configuration options. The injected CSS exploits stylis's \u0026 (scope reference) handling. :not(\u0026) escapes the #mermaid-xxx automatic scoping, applying styles to all page elements. Global at-rules (@font-face, @keyframes, @counter-style) are also injectable as stylis hoists them to top level. This allows page defacement and DOM attribute exfiltration via CSS :has() selectors. This vulnerability is fixed in 10.9.6 and 11.15.0.","ecosystems":["npm"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"Mermaid: Improper sanitization of configuration leads to CSS injection","id":"CVE-2026-41159","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"npm","product":null,"products":[],"type":"xss","year":"2026"},"n_packages":4,"n_references":5,"next":{"headline":"EspoCRM: Broken Access Control / IDOR in Note Pinning API allows unauthorized modification of notes","id":"CVE-2026-41160"},"packages":[{"ecosystem":"npm","fixed":["10.9.6"],"introduced":["0"],"last_affected":[],"package":"mermaid","purl":null,"source":"GHSA-87f9-hvmw-gh4p"},{"ecosystem":"npm","fixed":["10.9.6"],"introduced":["0"],"last_affected":[],"package":"mermaid","purl":"pkg:npm/mermaid","source":"GHSA-87f9-hvmw-gh4p"},{"ecosystem":"npm","fixed":["11.15.0"],"introduced":["11.0.0-alpha.1"],"last_affected":[],"package":"mermaid","purl":null,"source":"GHSA-87f9-hvmw-gh4p"},{"ecosystem":"npm","fixed":["11.15.0"],"introduced":["11.0.0-alpha.1"],"last_affected":[],"package":"mermaid","purl":"pkg:npm/mermaid","source":"GHSA-87f9-hvmw-gh4p"}],"prev":{"headline":"GPU DDK - Backed sparse PMRs are not handled by deferred free mechanism after shrink","id":"CVE-2026-41158"},"products":["mermaid"],"published":"2026-05-29","related":[{"cvss_score":7.2,"headline":"Incorrect sanitisation function leads to `XSS`","id":"CVE-2021-43861","kev_date_added":null,"published":"2021-12-30"},{"cvss_score":6.1,"headline":"Cross-site Scripting in Mermaid","id":"CVE-2021-35513","kev_date_added":null,"published":"2021-06-27"},{"cvss_score":5.3,"headline":"Mermaid Gantt Charts are vulnerable to an Infinite Loop DoS","id":"CVE-2026-41150","kev_date_added":null,"published":"2026-05-29"},{"cvss_score":5.1,"headline":"Mermaid does not properly sanitize architecture diagram iconText leading to XSS","id":"CVE-2025-54880","kev_date_added":null,"published":"2025-08-19"},{"cvss_score":4.1,"headline":"Arbitrary `CSS` injection into the generated graph affecting the container HTML in mermaid.js","id":"CVE-2022-31108","kev_date_added":null,"published":"2022-06-28"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-07-01","vendors":["mermaid-js"]},"summary":"Attackers can inject CSS to deface pages and exfiltrate DOM attributes via Mermaid configuration options, affecting applications using the library.","url":"https://insights.sbomify.com/CVE-2026-41159/"}