{"answers":{"affected":"16 open source packages ship an affected version, including @ckeditor/ckeditor5-engine, @ckeditor/ckeditor5-font and @ckeditor/ckeditor5-image. It affects 8 products.","exploited":"There is no known exploitation of CVE-2021-21391 in the wild and no public exploit code.","fix":"Upgrade @ckeditor/ckeditor5-engine to 27.0.0 or later.","what":"CVE-2021-21391 is a medium-severity vulnerability in ckeditor5, published on 29 Apr 2021."},"fix_prompt":"Check this codebase for CVE-2021-21391 and fix it if it is affected.\n\nWhat it is: CVE-2021-21391 is a medium-severity vulnerability in ckeditor5, published on 29 Apr 2021. \nExploitation: There is no known exploitation of CVE-2021-21391 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- @ckeditor/ckeditor5-engine (npm): affected all versions; fixed in 27.0.0\n- @ckeditor/ckeditor5-engine (npm): affected all versions; fixed in 27.0.0\n- @ckeditor/ckeditor5-font (npm): affected all versions; fixed in 27.0.0\n- @ckeditor/ckeditor5-font (npm): affected all versions; fixed in 27.0.0\n- @ckeditor/ckeditor5-image (npm): affected all versions; fixed in 27.0.0\n- @ckeditor/ckeditor5-image (npm): affected all versions; fixed in 27.0.0\n- @ckeditor/ckeditor5-list (npm): affected all versions; fixed in 27.0.0\n- @ckeditor/ckeditor5-list (npm): affected all versions; fixed in 27.0.0\n- @ckeditor/ckeditor5-markdown-gfm (npm): affected all versions; fixed in 27.0.0\n- @ckeditor/ckeditor5-markdown-gfm (npm): affected all versions; fixed in 27.0.0\n- @ckeditor/ckeditor5-media-embed (npm): affected all versions; fixed in 27.0.0\n- @ckeditor/ckeditor5-media-embed (npm): affected all versions; fixed in 27.0.0\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-2021-21391/ (Markdown: https://insights.sbomify.com/CVE-2021-21391/index.md)","id":"CVE-2021-21391","markdown":"https://insights.sbomify.com/CVE-2021-21391/index.md","name":"CVE-2021-21391","record":{"aliases":["GHSA-3rh3-wfr4-76mj","UBUNTU-CVE-2021-21391"],"analysis":null,"analysis_generated_by":null,"assigner":"GitHub_M","cpe":[{"product":"ckeditor5-engine","vendor":"ckeditor"},{"product":"ckeditor5-font","vendor":"ckeditor"},{"product":"ckeditor5-image","vendor":"ckeditor"},{"product":"ckeditor5-list","vendor":"ckeditor"},{"product":"ckeditor5-markdown-gfm","vendor":"ckeditor"},{"product":"ckeditor5-media-embed","vendor":"ckeditor"},{"product":"ckeditor5-paste-from-office","vendor":"ckeditor"},{"product":"ckeditor5-widget","vendor":"ckeditor"}],"cvss":{"score":6.5,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[{"id":"CWE-400","name":"Uncontrolled Resource Consumption"}],"description":"CKEditor 5 provides a WYSIWYG editing solution. This CVE affects the following npm packages: ckeditor5-engine, ckeditor5-font, ckeditor5-image, ckeditor5-list, ckeditor5-markdown-gfm, ckeditor5-media-embed, ckeditor5-paste-from-office, and ckeditor5-widget. Following an internal audit, a regular expression denial of service (ReDoS) vulnerability has been discovered in multiple CKEditor 5 packages. The vulnerability allowed to abuse particular regular expressions, which could cause a significant performance drop resulting in a browser tab freeze. It affects all users using the CKEditor 5 packages listed above at version \u003c= 26.0.0. The problem has been recognized and patched. The fix will be available in version 27.0.0.","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":"Regular expression Denial of Service in multiple packages","id":"CVE-2021-21391","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"npm","product":null,"products":[],"type":null,"year":"2021"},"n_packages":16,"n_references":9,"next":{"headline":"Open redirect via transitional IPv6 addresses on dual-stack networks","id":"CVE-2021-21392"},"packages":[{"ecosystem":"npm","fixed":["27.0.0"],"introduced":["0"],"last_affected":[],"package":"@ckeditor/ckeditor5-engine","purl":null,"source":"GHSA-3rh3-wfr4-76mj"},{"ecosystem":"npm","fixed":["27.0.0"],"introduced":["0"],"last_affected":[],"package":"@ckeditor/ckeditor5-engine","purl":"pkg:npm/%40ckeditor/ckeditor5-engine","source":"GHSA-3rh3-wfr4-76mj"},{"ecosystem":"npm","fixed":["27.0.0"],"introduced":["0"],"last_affected":[],"package":"@ckeditor/ckeditor5-font","purl":null,"source":"GHSA-3rh3-wfr4-76mj"},{"ecosystem":"npm","fixed":["27.0.0"],"introduced":["0"],"last_affected":[],"package":"@ckeditor/ckeditor5-font","purl":"pkg:npm/%40ckeditor/ckeditor5-font","source":"GHSA-3rh3-wfr4-76mj"},{"ecosystem":"npm","fixed":["27.0.0"],"introduced":["0"],"last_affected":[],"package":"@ckeditor/ckeditor5-image","purl":null,"source":"GHSA-3rh3-wfr4-76mj"},{"ecosystem":"npm","fixed":["27.0.0"],"introduced":["0"],"last_affected":[],"package":"@ckeditor/ckeditor5-image","purl":"pkg:npm/%40ckeditor/ckeditor5-image","source":"GHSA-3rh3-wfr4-76mj"},{"ecosystem":"npm","fixed":["27.0.0"],"introduced":["0"],"last_affected":[],"package":"@ckeditor/ckeditor5-list","purl":null,"source":"GHSA-3rh3-wfr4-76mj"},{"ecosystem":"npm","fixed":["27.0.0"],"introduced":["0"],"last_affected":[],"package":"@ckeditor/ckeditor5-list","purl":"pkg:npm/%40ckeditor/ckeditor5-list","source":"GHSA-3rh3-wfr4-76mj"},{"ecosystem":"npm","fixed":["27.0.0"],"introduced":["0"],"last_affected":[],"package":"@ckeditor/ckeditor5-markdown-gfm","purl":null,"source":"GHSA-3rh3-wfr4-76mj"},{"ecosystem":"npm","fixed":["27.0.0"],"introduced":["0"],"last_affected":[],"package":"@ckeditor/ckeditor5-markdown-gfm","purl":"pkg:npm/%40ckeditor/ckeditor5-markdown-gfm","source":"GHSA-3rh3-wfr4-76mj"},{"ecosystem":"npm","fixed":["27.0.0"],"introduced":["0"],"last_affected":[],"package":"@ckeditor/ckeditor5-media-embed","purl":null,"source":"GHSA-3rh3-wfr4-76mj"},{"ecosystem":"npm","fixed":["27.0.0"],"introduced":["0"],"last_affected":[],"package":"@ckeditor/ckeditor5-media-embed","purl":"pkg:npm/%40ckeditor/ckeditor5-media-embed","source":"GHSA-3rh3-wfr4-76mj"},{"ecosystem":"npm","fixed":["27.0.0"],"introduced":["0"],"last_affected":[],"package":"@ckeditor/ckeditor5-paste-from-office","purl":null,"source":"GHSA-3rh3-wfr4-76mj"},{"ecosystem":"npm","fixed":["27.0.0"],"introduced":["0"],"last_affected":[],"package":"@ckeditor/ckeditor5-paste-from-office","purl":"pkg:npm/%40ckeditor/ckeditor5-paste-from-office","source":"GHSA-3rh3-wfr4-76mj"},{"ecosystem":"npm","fixed":["27.0.0"],"introduced":["0"],"last_affected":[],"package":"@ckeditor/ckeditor5-widget","purl":null,"source":"GHSA-3rh3-wfr4-76mj"},{"ecosystem":"npm","fixed":["27.0.0"],"introduced":["0"],"last_affected":[],"package":"@ckeditor/ckeditor5-widget","purl":"pkg:npm/%40ckeditor/ckeditor5-widget","source":"GHSA-3rh3-wfr4-76mj"}],"prev":{"headline":"MITM modification of request bodies in MinIO","id":"CVE-2021-21390"},"products":["ckeditor5"],"published":"2021-04-29","related":[],"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":["ckeditor"]},"summary":null,"url":"https://insights.sbomify.com/CVE-2021-21391/"}