{"answers":{"affected":"It affects 2 products.","exploited":"There is no known exploitation of CVE-2021-3939 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2021-3939 is a high-severity use after free vulnerability in Canonical Ubuntu Linux, published on 17 Nov 2021. It can only be exploited from the same machine or local network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2021-3939 and fix it if it is affected.\n\nWhat it is: CVE-2021-3939 is a high-severity use after free vulnerability in Canonical Ubuntu Linux, published on 17 Nov 2021. It can only be exploited from the same machine or local network, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2021-3939 in the wild and no public exploit code.\n\nAffected product: Canonical Ubuntu Linux. 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-2021-3939/ (Markdown: https://insights.sbomify.com/CVE-2021-3939/index.md)","id":"CVE-2021-3939","markdown":"https://insights.sbomify.com/CVE-2021-3939/index.md","name":"CVE-2021-3939","record":{"aliases":["GHSA-jxh7-q7rm-43ww","UBUNTU-CVE-2021-3939","USN-5149-1"],"analysis":{"component_type":"operating_system","fix_type":"patch","impacts":["code_execution","denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Ubuntu accountsservice","requires_auth":"low_privilege","summary":"A use-after-free vulnerability in Ubuntu's accountsservice allows attackers to execute arbitrary code or cause a denial of service via the SetLanguage D-Bus function.","user_interaction":"not_required","vuln_class":"use_after_free"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"canonical","cpe":[{"product":"accountsservice","vendor":"canonical"},{"product":"ubuntu_linux","vendor":"canonical"}],"cvss":{"score":7.8,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H","version":"3.1"},"cwes":[{"id":"CWE-763","name":"Release of Invalid Pointer or Reference"},{"id":"CWE-590","name":"Free of Memory not on the Heap"}],"description":"Ubuntu-specific modifications to accountsservice (in patch file debian/patches/0010-set-language.patch) caused the fallback_locale variable, pointing to static storage, to be freed, in the user_change_language_authorized_cb function. This is reachable via the SetLanguage dbus function. This is fixed in versions 0.6.55-0ubuntu12~20.04.5, 0.6.55-0ubuntu13.3, 0.6.55-0ubuntu14.1.","ecosystems":[],"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":"Free of static data in accountsservice","id":"CVE-2021-3939","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"canonical:ubuntu_linux","products":["canonical:ubuntu_linux"],"type":"use_after_free","year":"2021"},"n_packages":0,"n_references":3,"next":{"headline":"DO NOT USE THIS CANDIDATE NUMBER.","id":"CVE-2021-3940"},"packages":[],"prev":{"headline":"Cross-site Scripting (XSS) - Generic in snipe/snipe-it","id":"CVE-2021-3938"},"products":["accountsservice"],"published":"2021-11-17","related":[{"cvss_score":8.1,"headline":"Use after free in AccountService","id":"CVE-2023-3297","kev_date_added":null,"published":"2023-09-01"},{"cvss_score":5.5,"headline":"Accountsservice incorrectly drops privileges","id":"CVE-2022-1804","kev_date_added":null,"published":"2025-03-25"},{"cvss_score":3.6,"headline":"Privilege escalation in n/a","id":"CVE-2011-4406","kev_date_added":null,"published":"2014-04-16"}],"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":"2024-09-16","vendors":["Ubuntu"]},"summary":"A use-after-free vulnerability in Ubuntu's accountsservice allows attackers to execute arbitrary code or cause a denial of service via the SetLanguage D-Bus function.","url":"https://insights.sbomify.com/CVE-2021-3939/"}