{"answers":{"affected":"It affects 1 product.","exploited":"It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-4128 exists.","fix":"No fix has been published for CVE-2021-4128 yet. Limit exposure of the affected software until one is available.","what":"CVE-2021-4128 is a medium-severity use after free vulnerability in Mozilla Firefox, published on 22 Dec 2022. 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-2021-4128 and fix it if it is affected.\n\nWhat it is: CVE-2021-4128 is a medium-severity use after free vulnerability in Mozilla Firefox, published on 22 Dec 2022. An attacker can exploit it over the internet without logging in, 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-2021-4128 exists.\n\nAffected product: Mozilla Firefox. 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-2021-4128/ (Markdown: https://insights.sbomify.com/CVE-2021-4128/index.md)","id":"CVE-2021-4128","markdown":"https://insights.sbomify.com/CVE-2021-4128/index.md","name":"CVE-2021-4128","record":{"aliases":["GHSA-qx74-qh3q-h8rj"],"analysis":{"component_type":"browser","fix_type":"upgrade","impacts":["code_execution","denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"Firefox browser","requires_auth":"none","summary":"A use-after-free vulnerability in Firefox on macOS allows attackers to cause memory corruption and potentially execute code via fullscreen transitions.","user_interaction":"required","vuln_class":"use_after_free"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"mozilla","cpe":[{"product":"firefox","vendor":"mozilla"}],"cvss":{"score":6.5,"severity":"medium","source":"cisa-adp","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-416","name":"Use After Free"}],"description":"When transitioning in and out of fullscreen mode, a graphics object was not correctly protected; resulting in memory corruption and a potentially exploitable crash.\u003cbr\u003e*This bug only affects Firefox on MacOS. Other operating systems are unaffected.*. This vulnerability affects Firefox \u003c 95.","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":"Use after free in Firefox","id":"CVE-2021-4128","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"mozilla:firefox","products":["mozilla:firefox"],"type":"use_after_free","year":"2021"},"n_packages":0,"n_references":2,"next":{"headline":"Memory corruption in Firefox","id":"CVE-2021-4129"},"packages":[],"prev":{"headline":"Other in Firefox ESR","id":"CVE-2021-4127"},"products":["Firefox"],"published":"2022-12-22","related":[{"cvss_score":10,"headline":"Mozilla Firefox and Thunderbird Sandbox Escape","id":"CVE-2019-11708","kev_date_added":"2022-05-23","published":"2019-07-23"},{"cvss_score":9.8,"headline":"Mozilla Multiple Products Remote Code Execution","id":"CVE-2010-3765","kev_date_added":"2025-10-06","published":"2010-10-27"},{"cvss_score":9.6,"headline":"Mozilla Firefox Use-After-Free","id":"CVE-2022-26486","kev_date_added":"2022-03-07","published":"2022-12-22"},{"cvss_score":8.8,"headline":"Mozilla Firefox Use-After-Free","id":"CVE-2022-26485","kev_date_added":"2022-03-07","published":"2022-12-22"},{"cvss_score":8.8,"headline":"Mozilla Firefox and Thunderbird Type Confusion","id":"CVE-2019-11707","kev_date_added":"2022-05-23","published":"2019-07-23"},{"cvss_score":8.1,"headline":"Mozilla Firefox And Thunderbird Use-After-Free","id":"CVE-2020-6819","kev_date_added":"2021-11-03","published":"2020-04-24"},{"cvss_score":8.1,"headline":"Mozilla Firefox And Thunderbird Use-After-Free","id":"CVE-2020-6820","kev_date_added":"2021-11-03","published":"2020-04-24"}],"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":"no","exploitation":"poc","technical_impact":"partial"},"state":"PUBLISHED","updated":"2025-04-16","vendors":["Mozilla"]},"summary":"A use-after-free vulnerability in Firefox on macOS allows attackers to cause memory corruption and potentially execute code via fullscreen transitions.","url":"https://insights.sbomify.com/CVE-2021-4128/"}