{"answers":{"affected":"4 open source packages ship an affected version, including highlight.js. It affects 3 products.","exploited":"There is no known exploitation of CVE-2020-26237 in the wild and no public exploit code.","fix":"Upgrade highlight.js to a fixed version for your release line: 9.18.2 or 10.1.2.","what":"CVE-2020-26237 is a medium-severity vulnerability in Debian Debian Linux, published on 24 Nov 2020. 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-2020-26237 and fix it if it is affected.\n\nWhat it is: CVE-2020-26237 is a medium-severity vulnerability in Debian Debian Linux, published on 24 Nov 2020. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.\nExploitation: There is no known exploitation of CVE-2020-26237 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- highlight.js (npm): affected all versions; fixed in 9.18.2\n- highlight.js (npm): affected all versions; fixed in 9.18.2\n- highlight.js (npm): affected from 10.0.0; fixed in 10.1.2\n- highlight.js (npm): affected from 10.0.0; fixed in 10.1.2\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-2020-26237/ (Markdown: https://insights.sbomify.com/CVE-2020-26237/index.md)","id":"CVE-2020-26237","markdown":"https://insights.sbomify.com/CVE-2020-26237/index.md","name":"CVE-2020-26237","record":{"aliases":["CLSA-2026-1788553382","DEBIAN-CVE-2020-26237","DLA-2511-1","GHSA-vfrc-7r7c-w9mx","UBUNTU-CVE-2020-26237","USN-8276-1"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":true,"product_category":"JavaScript syntax highlighter","requires_auth":"low_privilege","summary":"Prototype pollution in highlight.js allows attackers to cause denial of service via malicious HTML code blocks if user input is rendered.","user_interaction":"required","vuln_class":"other"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"debian_linux","vendor":"debian"},{"product":"highlight.js","vendor":"highlightjs"},{"product":"mysql_enterprise_monitor","vendor":"oracle"}],"cvss":{"score":5.8,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:N/I:H/A:N","version":"3.1"},"cwes":[{"id":"CWE-471","name":"Modification of Assumed-Immutable Data (MAID)"}],"description":"Highlight.js is a syntax highlighter written in JavaScript. Highlight.js versions before 9.18.2 and 10.1.2 are vulnerable to Prototype Pollution. A malicious HTML code block can be crafted that will result in prototype pollution of the base object's prototype during highlighting. If you allow users to insert custom HTML code blocks into your page/app via parsing Markdown code blocks (or similar) and do not filter the language names the user can provide you may be vulnerable. The pollution should just be harmless data but this can cause problems for applications not expecting these properties to exist and can result in strange behavior or application crashes, i.e. a potential DOS vector. If your website or application does not render user provided data it should be unaffected. Versions 9.18.2 and 10.1.2 and newer include fixes for this vulnerability. If you are using version 7 or 8 you are encouraged to upgrade to a newer release.","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":"Prototype Pollution in highlight.js","id":"CVE-2020-26237","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"npm","product":"debian:debian_linux","products":["debian:debian_linux","oracle:mysql_enterprise_monitor"],"type":"other","year":"2020"},"n_packages":4,"n_references":6,"next":{"headline":"Critical vulnerability found in cron-utils","id":"CVE-2020-26238"},"packages":[{"ecosystem":"npm","fixed":["9.18.2"],"introduced":["0"],"last_affected":[],"package":"highlight.js","purl":null,"source":"GHSA-vfrc-7r7c-w9mx"},{"ecosystem":"npm","fixed":["9.18.2"],"introduced":["0"],"last_affected":[],"package":"highlight.js","purl":"pkg:npm/highlight.js","source":"GHSA-vfrc-7r7c-w9mx"},{"ecosystem":"npm","fixed":["10.1.2"],"introduced":["10.0.0"],"last_affected":[],"package":"highlight.js","purl":null,"source":"GHSA-vfrc-7r7c-w9mx"},{"ecosystem":"npm","fixed":["10.1.2"],"introduced":["10.0.0"],"last_affected":[],"package":"highlight.js","purl":"pkg:npm/highlight.js","source":"GHSA-vfrc-7r7c-w9mx"}],"prev":{"headline":"Verification Code Hijacking in ScratchVerifier","id":"CVE-2020-26236"},"products":["highlight.js"],"published":"2020-11-24","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":"2024-08-04","vendors":["highlightjs"]},"summary":"Prototype pollution in highlight.js allows attackers to cause denial of service via malicious HTML code blocks if user input is rendered.","url":"https://insights.sbomify.com/CVE-2020-26237/"}