{"answers":{"affected":"1 open source package ship an affected version, including mdex.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-54889 exists.","fix":"Upgrade mdex to 0.13.2 or later.","what":"CVE-2026-54889 is a medium-severity cross-site scripting vulnerability in leandrocp mdex, published on 29 Jun 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-2026-54889 and fix it if it is affected.\n\nWhat it is: CVE-2026-54889 is a medium-severity cross-site scripting vulnerability in leandrocp mdex, published on 29 Jun 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: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-54889 exists.\n\nAffected packages and fixed versions:\n- mdex (Hex): affected from 0.8.3; fixed in 0.13.2\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-2026-54889/ (Markdown: https://insights.sbomify.com/CVE-2026-54889/index.md)","id":"CVE-2026-54889","markdown":"https://insights.sbomify.com/CVE-2026-54889/index.md","name":"CVE-2026-54889","record":{"aliases":["EEF-CVE-2026-54889","GHSA-4383-7xfp-gpph"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["code_execution"],"network_reachable":"yes","non_default_config":false,"product_category":"Elixir Markdown library","requires_auth":"none","summary":"Attackers can inject JavaScript via unsanitized URL schemes in Markdown links, leading to XSS when rendered by downstream clients.","user_interaction":"required","vuln_class":"xss"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"EEF","cpe":[],"cvss":{"score":5.1,"severity":"medium","source":"cna","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N","version":"4.0"},"cwes":[{"id":"CWE-79","name":"Improper Neutralization of Input During Web Page Generation"}],"description":"Improper Neutralization of Input During Web Page Generation (XSS) vulnerability in leandrocp mdex allows cross-site scripting via unsanitized URL schemes in Quill Delta output.\n\n'Elixir.MDEx':to_delta/2 converts Markdown into a Quill Delta. 'Elixir.MDEx.DeltaConverter':default_convert_node/3 in lib/mdex/delta_converter.ex copies the URL of a link, wikilink, or image node directly from the parsed Markdown into the Delta \"link\" or \"image\" attribute without applying a scheme allowlist or any normalization.\n\nAn attacker who controls the Markdown text can supply a javascript: URL (for example [click](javascript:alert(document.cookie))) that survives verbatim into the Delta attribute. When the Delta is rendered to HTML by a downstream renderer (such as quill-delta-to-html or the Quill client), the attribute becomes an \u003ca href\u003e or \u003cimg src\u003e, and the javascript: scheme executes in the browser of anyone who views the rendered content. The link and wikilink cases are the strongest vectors because javascript: in an href executes on click; the image case is lower impact because javascript: in \u003cimg src\u003e generally does not execute in modern browsers.\n\nThis issue affects mdex: from 0.8.3 before 0.13.2.","ecosystems":["Hex"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":true,"headline":"Unsanitized URL schemes in MDEx Quill Delta output allow javascript: injection (XSS)","id":"CVE-2026-54889","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Hex","product":null,"products":[],"type":"xss","year":"2026"},"n_packages":1,"n_references":4,"next":{"headline":"BEAM VM crash via integer underflow in binary_to_term BIT_BINARY_EXT decoding","id":"CVE-2026-54890"},"packages":[{"ecosystem":"Hex","fixed":["0.13.2"],"introduced":["0.8.3"],"last_affected":[],"package":"mdex","purl":"pkg:hex/mdex","source":"EEF-CVE-2026-54889"}],"prev":{"headline":"Uncontrolled recursion over deeply nested Markdown crashes the BEAM in mdex","id":"CVE-2026-54888"},"products":["mdex"],"published":"2026-06-29","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"Erlang Ecosystem Foundation","prefix":"EEF"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"poc","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-06-30","vendors":["leandrocp"]},"summary":"Attackers can inject JavaScript via unsanitized URL schemes in Markdown links, leading to XSS when rendered by downstream clients.","url":"https://insights.sbomify.com/CVE-2026-54889/"}