{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2021-47013 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2021-47013 is a critical use after free vulnerability in Linux kernel, published on 28 Feb 2024. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2021-47013 and fix it if it is affected.\n\nWhat it is: CVE-2021-47013 is a critical use after free vulnerability in Linux kernel, published on 28 Feb 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2021-47013 in the wild and no public exploit code.\n\nAffected product: Linux kernel. 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-2021-47013/ (Markdown: https://insights.sbomify.com/CVE-2021-47013/index.md)","id":"CVE-2021-47013","markdown":"https://insights.sbomify.com/CVE-2021-47013/index.md","name":"CVE-2021-47013","record":{"aliases":["DEBIAN-CVE-2021-47013","GHSA-3ch6-f277-559q","UBUNTU-CVE-2021-47013"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["code_execution","denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"Linux kernel","requires_auth":"none","summary":"A use-after-free vulnerability in the Linux kernel's EMAC driver allows attackers to potentially execute code or cause a denial of service.","user_interaction":"not_required","vuln_class":"use_after_free"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[{"product":"linux_kernel","vendor":"linux"}],"cvss":{"score":9.8,"severity":"critical","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"cwes":[{"id":"CWE-416","name":"Use After Free"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet:emac/emac-mac: Fix a use after free in emac_mac_tx_buf_send\n\nIn emac_mac_tx_buf_send, it calls emac_tx_fill_tpd(..,skb,..).\nIf some error happens in emac_tx_fill_tpd(), the skb will be freed via\ndev_kfree_skb(skb) in error branch of emac_tx_fill_tpd().\nBut the freed skb is still used via skb-\u003elen by netdev_sent_queue(,skb-\u003elen).\n\nAs i observed that emac_tx_fill_tpd() haven't modified the value of skb-\u003elen,\nthus my patch assigns skb-\u003elen to 'len' before the possible free and\nuse 'len' instead of skb-\u003elen later.","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":"net:emac/emac-mac: Fix a use after free in emac_mac_tx_buf_send","id":"CVE-2021-47013","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"use_after_free","year":"2021"},"n_packages":0,"n_references":8,"next":{"headline":"net/sched: act_ct: fix wild memory access when clearing fragments","id":"CVE-2021-47014"},"packages":[],"prev":{"headline":"RDMA/siw: Fix a use after free in siw_alloc_mr","id":"CVE-2021-47012"},"products":["Linux"],"published":"2024-02-28","related":[{"cvss_score":8.8,"headline":"Linux Kernel Out-of-Bounds Write","id":"CVE-2026-53266","kev_date_added":"2026-09-18","published":"2026-06-25"},{"cvss_score":8.8,"headline":"Linux Kernel Improper Input Validation","id":"CVE-2013-6282","kev_date_added":"2022-09-15","published":"2013-11-19"},{"cvss_score":8.4,"headline":"Linux Kernel Heap-Based Buffer Overflow","id":"CVE-2022-0185","kev_date_added":"2024-08-21","published":"2022-02-11"},{"cvss_score":8.4,"headline":"Linux Kernel Privilege Escalation","id":"CVE-2013-2094","kev_date_added":"2022-09-15","published":"2013-05-14"},{"cvss_score":7.8,"headline":"Linux Kernel Unspecified","id":"CVE-2026-53362","kev_date_added":"2026-08-27","published":"2026-07-04"},{"cvss_score":7.8,"headline":"Linux Kernel Missing Initialization of a Variable","id":"CVE-2026-46300","kev_date_added":"2026-10-28","published":"2026-05-23"},{"cvss_score":7.8,"headline":"Linux Kernel Race Condition","id":"CVE-2025-39964","kev_date_added":"2026-09-18","published":"2025-10-13"}],"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":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-08-05","vendors":["Linux"]},"summary":"A use-after-free vulnerability in the Linux kernel's EMAC driver allows attackers to potentially execute code or cause a denial of service.","url":"https://insights.sbomify.com/CVE-2021-47013/"}