{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2021-43855 in the wild and no public exploit code.","fix":"No fix has been published for CVE-2021-43855 yet. Limit exposure of the affected software until one is available.","what":"CVE-2021-43855 is a high-severity cross-site scripting vulnerability in Requarks wiki, published on 27 Dec 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-2021-43855 and fix it if it is affected.\n\nWhat it is: CVE-2021-43855 is a high-severity cross-site scripting vulnerability in Requarks wiki, published on 27 Dec 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-2021-43855 in the wild and no public exploit code.\n\nAffected product: Requarks wiki. 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-2021-43855/ (Markdown: https://insights.sbomify.com/CVE-2021-43855/index.md)","id":"CVE-2021-43855","markdown":"https://insights.sbomify.com/CVE-2021-43855/index.md","name":"CVE-2021-43855","record":{"aliases":["GHSA-4893-pj5w-3hq9"],"analysis":{"component_type":"web_application","fix_type":"patch","impacts":["code_execution"],"network_reachable":"yes","non_default_config":false,"product_category":"Wiki.js application","requires_auth":"none","summary":"A malicious user can upload a crafted SVG file to execute arbitrary JavaScript in other users' browsers when the file is viewed directly.","user_interaction":"required","vuln_class":"xss"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"wiki.js","vendor":"requarks"}],"cvss":{"score":8.2,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N","version":"3.1"},"cwes":[{"id":"CWE-79","name":"Improper Neutralization of Input During Web Page Generation"}],"description":"Wiki.js is a wiki app built on node.js. Wiki.js 2.5.263 and earlier is vulnerable to stored cross-site scripting through a SVG file upload made via a custom request with a fake MIME type. By creating a crafted SVG file, a malicious Wiki.js user may stage a stored cross-site scripting attack. This allows the attacker to execute malicious JavaScript when the SVG is viewed directly by other users. Scripts do not execute when loaded inside a page via normal `\u003cimg\u003e` tags. The malicious SVG can only be uploaded by crafting a custom request to the server with a fake MIME type. A patch in version 2.5.264 fixes this vulnerability by adding an additional file extension verification check to the optional (enabled by default) SVG sanitization step to all file uploads that match the SVG mime type. As a workaround, disable file upload for all non-trusted users.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":false,"headline":"Stored XSS via SVG in Requarks/wiki","id":"CVE-2021-43855","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"xss","year":"2021"},"n_packages":0,"n_references":3,"next":{"headline":"Stored XSS in non-image uploads in Requarks/wiki","id":"CVE-2021-43856"},"packages":[],"prev":{"headline":"Inefficient Regular Expression Complexity in nltk","id":"CVE-2021-43854"},"products":["wiki"],"published":"2021-12-27","related":[{"cvss_score":9.1,"headline":"Security feature bypass in n/a","id":"CVE-2025-56643","kev_date_added":null,"published":"2025-11-18"},{"cvss_score":8.6,"headline":"Wiki.js: Privilege Escalation via Missing Group Validation in users.update","id":"CVE-2026-44224","kev_date_added":null,"published":"2026-05-12"},{"cvss_score":8.6,"headline":"Directory Traversal in Wiki.js","id":"CVE-2020-15236","kev_date_added":null,"published":"2020-10-05"},{"cvss_score":8.2,"headline":"Stored XSS in non-image uploads in Requarks/wiki","id":"CVE-2021-43856","kev_date_added":null,"published":"2021-12-27"},{"cvss_score":8.1,"headline":"Improper write access check in Requarks/wiki","id":"CVE-2022-23654","kev_date_added":null,"published":"2022-02-22"},{"cvss_score":7.6,"headline":"XSS in Wiki.js","id":"CVE-2021-21383","kev_date_added":null,"published":"2021-03-18"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"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":"2024-08-04","vendors":["Requarks"]},"summary":"A malicious user can upload a crafted SVG file to execute arbitrary JavaScript in other users' browsers when the file is viewed directly.","url":"https://insights.sbomify.com/CVE-2021-43855/"}