{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2021-3492 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2021-3492 is a high-severity use after free vulnerability in Canonical Ubuntu Linux, published on 17 Apr 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-2021-3492 and fix it if it is affected.\n\nWhat it is: CVE-2021-3492 is a high-severity use after free vulnerability in Canonical Ubuntu Linux, published on 17 Apr 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-2021-3492 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-2021-3492/ (Markdown: https://insights.sbomify.com/CVE-2021-3492/index.md)","id":"CVE-2021-3492","markdown":"https://insights.sbomify.com/CVE-2021-3492/index.md","name":"CVE-2021-3492","record":{"aliases":["GHSA-hr5j-7qj8-mpp3","LSN-0077-1","UBUNTU-CVE-2021-3492"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["privilege_escalation","denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Ubuntu Linux kernel","requires_auth":"low_privilege","summary":"An attacker can exploit a double-free vulnerability in the Ubuntu shiftfs file system to cause denial of service or execute arbitrary code with kernel privileges.","user_interaction":"not_required","vuln_class":"use_after_free"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"canonical","cpe":[{"product":"ubuntu_linux","vendor":"canonical"}],"cvss":{"score":8.8,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","version":"3.1"},"cwes":[{"id":"CWE-415","name":"Double Free"},{"id":"CWE-401","name":"Missing Release of Memory after Effective Lifetime"}],"description":"Shiftfs, an out-of-tree stacking file system included in Ubuntu Linux kernels, did not properly handle faults occurring during copy_from_user() correctly. These could lead to either a double-free situation or memory not being freed at all. An attacker could use this to cause a denial of service (kernel memory exhaustion) or gain privileges via executing arbitrary code. AKA ZDI-CAN-13562.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":"2021-06-28","github_poc":1,"max_poc_stars":42,"metasploit":0,"nuclei":0,"refs":[{"date":"2021-06-28T09:43:31Z","kind":"github_poc","ref":"https://github.com/synacktiv/CVE-2021-3492","stars":42,"title":"PoC for CVE-2021-3492 used at Pwn2Own 2021"}],"tier":"poc_unverified"},"has_fix":true,"headline":"Ubuntu linux kernel shiftfs file system double free vulnerability","id":"CVE-2021-3492","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":6,"next":{"headline":"Linux Kernel Privilege Escalation","id":"CVE-2021-3493"},"packages":[],"prev":{"headline":"Linux kernel io_uring PROVIDE_BUFFERS MAX_RW_COUNT bypass","id":"CVE-2021-3491"},"products":["Linux kernel"],"published":"2021-04-17","related":[{"cvss_score":9.8,"headline":"SaltStack Salt Authentication Bypass","id":"CVE-2020-11651","kev_date_added":"2021-11-03","published":"2020-04-30"},{"cvss_score":9.8,"headline":"OpenSMTPD Remote Code Execution","id":"CVE-2020-7247","kev_date_added":"2022-03-25","published":"2020-01-29"},{"cvss_score":9.8,"headline":"Exim Out-of-bounds Write","id":"CVE-2019-16928","kev_date_added":"2022-03-03","published":"2019-09-27"},{"cvss_score":9.8,"headline":"Exim Buffer Overflow","id":"CVE-2018-6789","kev_date_added":"2021-11-03","published":"2018-02-08"},{"cvss_score":9.8,"headline":"Oracle Java SE and Java SE Embedded Remote Code Execution","id":"CVE-2015-2590","kev_date_added":"2022-03-03","published":"2015-07-16"},{"cvss_score":9.8,"headline":"Oracle JRE Remote Code Execution","id":"CVE-2013-0422","kev_date_added":"2022-05-25","published":"2013-01-10"},{"cvss_score":9.8,"headline":"Oracle Java SE Runtime Environment (JRE) Arbitrary Code Execution","id":"CVE-2011-3544","kev_date_added":"2022-03-03","published":"2011-10-19"}],"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)"},{"class":"open","licence":"CC0","name":"PoC-in-GitHub"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2024-09-17","vendors":["Ubuntu"]},"summary":"An attacker can exploit a double-free vulnerability in the Ubuntu shiftfs file system to cause denial of service or execute arbitrary code with kernel privileges.","url":"https://insights.sbomify.com/CVE-2021-3492/"}