{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2024-26921 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2024-26921 is a high-severity use after free vulnerability in Linux kernel, published on 18 Apr 2024. 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-2024-26921 and fix it if it is affected.\n\nWhat it is: CVE-2024-26921 is a high-severity use after free vulnerability in Linux kernel, published on 18 Apr 2024. 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-2024-26921 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-2024-26921/ (Markdown: https://insights.sbomify.com/CVE-2024-26921/index.md)","id":"CVE-2024-26921","markdown":"https://insights.sbomify.com/CVE-2024-26921/index.md","name":"CVE-2024-26921","record":{"aliases":["BELL-CVE-2024-26921","DEBIAN-CVE-2024-26921","GHSA-4vg2-58j7-gmw7","UBUNTU-CVE-2024-26921"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service","code_execution"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel","requires_auth":"low_privilege","summary":"A use-after-free vulnerability in the Linux kernel's IP defragmentation allows attackers to cause denial of service or potentially execute code.","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":7.8,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\ninet: inet_defrag: prevent sk release while still in use\n\nip_local_out() and other functions can pass skb-\u003esk as function argument.\n\nIf the skb is a fragment and reassembly happens before such function call\nreturns, the sk must not be released.\n\nThis affects skb fragments reassembled via netfilter or similar\nmodules, e.g. openvswitch or ct_act.c, when run as part of tx pipeline.\n\nEric Dumazet made an initial analysis of this bug.  Quoting Eric:\n  Calling ip_defrag() in output path is also implying skb_orphan(),\n  which is buggy because output path relies on sk not disappearing.\n\n  A relevant old patch about the issue was :\n  8282f27449bf (\"inet: frag: Always orphan skbs inside ip_defrag()\")\n\n  [..]\n\n  net/ipv4/ip_output.c depends on skb-\u003esk being set, and probably to an\n  inet socket, not an arbitrary one.\n\n  If we orphan the packet in ipvlan, then downstream things like FQ\n  packet scheduler will not work properly.\n\n  We need to change ip_defrag() to only use skb_orphan() when really\n  needed, ie whenever frag_list is going to be used.\n\nEric suggested to stash sk in fragment queue and made an initial patch.\nHowever there is a problem with this:\n\nIf skb is refragmented again right after, ip_do_fragment() will copy\nhead-\u003esk to the new fragments, and sets up destructor to sock_wfree.\nIOW, we have no choice but to fix up sk_wmem accouting to reflect the\nfully reassembled skb, else wmem will underflow.\n\nThis change moves the orphan down into the core, to last possible moment.\nAs ip_defrag_offset is aliased with sk_buff-\u003esk member, we must move the\noffset into the FRAG_CB, else skb-\u003esk gets clobbered.\n\nThis allows to delay the orphaning long enough to learn if the skb has\nto be queued or if the skb is completing the reasm queue.\n\nIn the former case, things work as before, skb is orphaned.  This is\nsafe because skb gets queued/stolen and won't continue past reasm engine.\n\nIn the latter case, we will steal the skb-\u003esk reference, reattach it to\nthe head skb, and fix up wmem accouting when inet_frag inflates truesize.","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":"inet: inet_defrag: prevent sk release while still in use","id":"CVE-2024-26921","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"use_after_free","year":"2024"},"n_packages":0,"n_references":7,"next":{"headline":"drm/amdgpu: validate the parameters of bo mapping operations more clearly","id":"CVE-2024-26922"},"packages":[],"prev":{"headline":"tracing/trigger: Fix to return error if failed to alloc snapshot","id":"CVE-2024-26920"},"products":["Linux"],"published":"2024-04-18","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":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"yes","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-08-05","vendors":["Linux"]},"summary":"A use-after-free vulnerability in the Linux kernel's IP defragmentation allows attackers to cause denial of service or potentially execute code.","url":"https://insights.sbomify.com/CVE-2024-26921/"}