{"answers":{"affected":"3 open source packages ship an affected version, including bleach. It affects 1 product.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2020-6817 exists.","fix":"Upgrade bleach to 3.1.4 or later.","what":"CVE-2020-6817 is a high-severity denial of service vulnerability in Mozilla Bleach, published on 16 Feb 2023. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2020-6817 and fix it if it is affected.\n\nWhat it is: CVE-2020-6817 is a high-severity denial of service vulnerability in Mozilla Bleach, published on 16 Feb 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2020-6817 exists.\n\nAffected packages and fixed versions:\n- bleach (PyPI): affected all versions; fixed in 3.1.4\n- bleach (PyPI): affected all versions; fixed in 3.1.4\n- bleach (PyPI): affected all versions; fixed in 3.1.4\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-2020-6817/ (Markdown: https://insights.sbomify.com/CVE-2020-6817/index.md)","id":"CVE-2020-6817","markdown":"https://insights.sbomify.com/CVE-2020-6817/index.md","name":"CVE-2020-6817","record":{"aliases":["DEBIAN-CVE-2020-6817","DLA-2167-1","GHSA-vqhp-cxgc-6wmm","PYSEC-2020-340","SNYK-PYTHON-BLEACH-561754","UBUNTU-CVE-2020-6817"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":true,"product_category":"Python HTML sanitization library","requires_auth":"none","summary":"Attackers can cause denial of service in applications using Bleach by exploiting ReDoS in style attribute parsing when specific tags and styles are allowed.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"mozilla","cpe":[{"product":"bleach","vendor":"mozilla"}],"cvss":{"score":7.5,"severity":"high","source":"cisa-adp","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[{"id":"CWE-1333","name":"Inefficient Regular Expression Complexity"}],"description":"bleach.clean behavior parsing style attributes could result in a regular expression denial of service (ReDoS). Calls to bleach.clean with an allowed tag with an allowed style attribute are vulnerable to ReDoS. For example, bleach.clean(..., attributes={'a': ['style']}).","ecosystems":["PyPI"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"weaponised"},"has_fix":true,"headline":"regular expression denial-of-service (ReDoS) in Bleach","id":"CVE-2020-6817","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"PyPI","product":null,"products":[],"type":"denial_of_service","year":"2020"},"n_packages":3,"n_references":2,"next":{"headline":"Mozilla Firefox And Thunderbird Use-After-Free","id":"CVE-2020-6819"},"packages":[{"ecosystem":"PyPI","fixed":["3.1.4"],"introduced":["0"],"last_affected":[],"package":"bleach","purl":null,"source":"GHSA-vqhp-cxgc-6wmm"},{"ecosystem":"PyPI","fixed":["3.1.4"],"introduced":["0"],"last_affected":[],"package":"bleach","purl":"pkg:pypi/bleach","source":"GHSA-vqhp-cxgc-6wmm"},{"ecosystem":"PyPI","fixed":["3.1.4"],"introduced":["0"],"last_affected":[],"package":"bleach","purl":"pkg:pypi/bleach","source":"PYSEC-2020-340"}],"prev":{"headline":"Bleach vulnerable to mutation XSS via whitelisted math or svg and raw tag","id":"CVE-2020-6816"},"products":["Mozilla Bleach"],"published":"2023-02-16","related":[{"cvss_score":9.8,"headline":"Bleach URI Scheme Restriction Bypass","id":"CVE-2018-7753","kev_date_added":null,"published":"2018-03-07"},{"cvss_score":6.1,"headline":"Cross-site scripting in Bleach","id":"CVE-2021-23980","kev_date_added":null,"published":"2023-02-16"}],"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":"CC BY 4.0","name":"PyPA Advisory Database","prefix":"PYSEC"},{"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":"yes","exploitation":"poc","technical_impact":"partial"},"state":"PUBLISHED","updated":"2025-03-19","vendors":["Mozilla"]},"summary":"Attackers can cause denial of service in applications using Bleach by exploiting ReDoS in style attribute parsing when specific tags and styles are allowed.","url":"https://insights.sbomify.com/CVE-2020-6817/"}