{"answers":{"affected":"","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-47837 exists.","fix":"No fix has been published for CVE-2021-47837 yet. Limit exposure of the affected software until one is available.","what":"CVE-2021-47837 is a medium-severity cross-site scripting vulnerability in amitmerchant1990 Markdownify, published on 16 Jan 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link."},"fix_prompt":"Check this codebase for CVE-2021-47837 and fix it if it is affected.\n\nWhat it is: CVE-2021-47837 is a medium-severity cross-site scripting vulnerability in amitmerchant1990 Markdownify, published on 16 Jan 2026. Any signed-in user can exploit it over the network, 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-2021-47837 exists.\n\nAffected product: amitmerchant1990 Markdownify. No package-level version data is available, so check the vendor advisory linked from the reference page.\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-2021-47837/ (Markdown: https://insights.sbomify.com/CVE-2021-47837/index.md)","id":"CVE-2021-47837","markdown":"https://insights.sbomify.com/CVE-2021-47837/index.md","name":"CVE-2021-47837","record":{"aliases":["GHSA-rfvr-hv7q-m46g"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["code_execution"],"network_reachable":"yes","non_default_config":false,"product_category":"Markdown rendering library","requires_auth":"low_privilege","summary":"Attackers can inject malicious scripts into markdown files that execute when rendered, potentially leading to remote code execution.","user_interaction":"required","vuln_class":"xss"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"VulnCheck","cpe":[],"cvss":{"score":5.1,"severity":"medium","source":"cna","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/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":"Markdownify 1.2.0 contains a persistent cross-site scripting vulnerability that allows attackers to store malicious payloads within markdown files. Attackers can upload crafted markdown files with embedded scripts that execute when the file is opened, potentially enabling remote code execution.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":null,"headline":"Markdownify 1.2.0 - Persistent Cross-Site Scripting","id":"CVE-2021-47837","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"xss","year":"2021"},"n_packages":0,"n_references":4,"next":{"headline":"Markright 1.0 - Persistent Cross-Site Scripting","id":"CVE-2021-47838"},"packages":[],"prev":{"headline":"Markdown Explorer 0.1.1 - Persistent Cross-Site Scripting","id":"CVE-2021-47836"},"products":["Markdownify"],"published":"2026-01-16","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"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":"2026-03-05","vendors":["amitmerchant1990"]},"summary":"Attackers can inject malicious scripts into markdown files that execute when rendered, potentially leading to remote code execution.","url":"https://insights.sbomify.com/CVE-2021-47837/"}