{"answers":{"affected":"2 open source packages ship an affected version, including xmldom. It affects 2 products.","exploited":"There is no known exploitation of CVE-2021-21366 in the wild and no public exploit code.","fix":"Upgrade xmldom to 0.5.0 or later.","what":"CVE-2021-21366 is a medium-severity vulnerability in Debian Debian Linux, published on 12 Mar 2021. 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-2021-21366 and fix it if it is affected.\n\nWhat it is: CVE-2021-21366 is a medium-severity vulnerability in Debian Debian Linux, published on 12 Mar 2021. 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-2021-21366 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- xmldom (npm): affected all versions; fixed in 0.5.0\n- xmldom (npm): affected all versions; fixed in 0.5.0\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-2021-21366/ (Markdown: https://insights.sbomify.com/CVE-2021-21366/index.md)","id":"CVE-2021-21366","markdown":"https://insights.sbomify.com/CVE-2021-21366/index.md","name":"CVE-2021-21366","record":{"aliases":["DEBIAN-CVE-2021-21366","GHSA-h6q6-9hqw-rwfv","UBUNTU-CVE-2021-21366"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["code_execution","data_read"],"network_reachable":"yes","non_default_config":false,"product_category":"JavaScript XML library","requires_auth":"none","summary":"Attackers can exploit XML parsing flaws in xmldom to cause unexpected syntactic changes, potentially leading to code execution or data exposure.","user_interaction":"required","vuln_class":"xxe"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"debian_linux","vendor":"debian"},{"product":"xmldom","vendor":"xmldom_project"}],"cvss":{"score":4.3,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N","version":"3.1"},"cwes":[{"id":"CWE-436","name":"Interpretation Conflict"},{"id":"CWE-115","name":"Misinterpretation of Input"}],"description":"xmldom is a pure JavaScript W3C standard-based (XML DOM Level 2 Core) DOMParser and XMLSerializer module. xmldom versions 0.4.0 and older do not correctly preserve system identifiers, FPIs or namespaces when repeatedly parsing and serializing maliciously crafted documents. This may lead to unexpected syntactic changes during XML processing in some downstream applications. This is fixed in version 0.5.0. As a workaround downstream applications can validate the input and reject the maliciously crafted documents.","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":"Misinterpretation of malicious XML input","id":"CVE-2021-21366","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"npm","product":"debian:debian_linux","products":["debian:debian_linux"],"type":"xxe","year":"2021"},"n_packages":2,"n_references":5,"next":{"headline":"Incorrect Authorization in switchboard-plug-bluetooth","id":"CVE-2021-21367"},"packages":[{"ecosystem":"npm","fixed":["0.5.0"],"introduced":["0"],"last_affected":[],"package":"xmldom","purl":null,"source":"GHSA-h6q6-9hqw-rwfv"},{"ecosystem":"npm","fixed":["0.5.0"],"introduced":["0"],"last_affected":[],"package":"xmldom","purl":"pkg:npm/xmldom","source":"GHSA-h6q6-9hqw-rwfv"}],"prev":{"headline":"Cross-Site Scripting in Content Rendering","id":"CVE-2021-21365"},"products":["xmldom"],"published":"2021-03-12","related":[{"cvss_score":10,"headline":"ProFTPD Improper Access Control","id":"CVE-2015-3306","kev_date_added":"2026-10-08","published":"2015-05-18"},{"cvss_score":9.9,"headline":"RoundCube Webmail Deserialization of Untrusted Data","id":"CVE-2025-49113","kev_date_added":"2026-02-20","published":"2025-06-02"},{"cvss_score":9.8,"headline":"GNU InetUtils Argument Injection","id":"CVE-2026-24061","kev_date_added":"2026-01-26","published":"2026-01-21"},{"cvss_score":9.8,"headline":"Linux Kernel Improper Check for Unusual or Exceptional Conditions","id":"CVE-2025-39682","kev_date_added":"2026-09-18","published":"2025-09-05"},{"cvss_score":9.8,"headline":"Mozilla Firefox Use-After-Free","id":"CVE-2024-9680","kev_date_added":"2024-10-15","published":"2024-10-09"},{"cvss_score":9.8,"headline":"RARLAB UnRAR Directory Traversal","id":"CVE-2022-30333","kev_date_added":"2022-08-09","published":"2022-05-09"},{"cvss_score":9.8,"headline":"Roundcube Webmail SQL Injection","id":"CVE-2021-44026","kev_date_added":"2023-06-22","published":"2021-11-19"}],"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":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2024-08-03","vendors":["xmldom"]},"summary":"Attackers can exploit XML parsing flaws in xmldom to cause unexpected syntactic changes, potentially leading to code execution or data exposure.","url":"https://insights.sbomify.com/CVE-2021-21366/"}