{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-46116 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-46116 is a high-severity use after free vulnerability in Linux kernel, published on 28 May 2026. 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-2026-46116 and fix it if it is affected.\n\nWhat it is: CVE-2026-46116 is a high-severity use after free vulnerability in Linux kernel, published on 28 May 2026. 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-2026-46116 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-2026-46116/ (Markdown: https://insights.sbomify.com/CVE-2026-46116/index.md)","id":"CVE-2026-46116","markdown":"https://insights.sbomify.com/CVE-2026-46116/index.md","name":"CVE-2026-46116","record":{"aliases":["AZL-89070","BELL-CVE-2026-46116","DEBIAN-CVE-2026-46116","GHSA-96hg-7p79-ggx2","ROOT-OS-DEBIAN-11-CVE-2026-46116","ROOT-OS-DEBIAN-12-CVE-2026-46116","ROOT-OS-UBUNTU-2204-CVE-2026-46116","ROOT-OS-UBUNTU-2404-CVE-2026-46116","UBUNTU-CVE-2026-46116"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["code_execution","denial_of_service"],"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 xfrm subsystem allows attackers to cause denial of service or potentially execute code via crafted network namespace cleanup operations.","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":[{"id":"CWE-763","name":"Release of Invalid Pointer or Reference"},{"id":"CWE-416","name":"Use After Free"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: defensively unhash xfrm_state lists in __xfrm_state_delete\n\nKASAN reproduces a slab-use-after-free in __xfrm_state_delete()'s\nhlist_del_rcu calls under syzkaller load on linux-6.12.y stable\n(reproduced on 6.12.47, also reachable via the same code path on\ntorvalds/master and on the ipsec tree). Nine unique signatures cluster\nin the xfrm_state lifecycle, the load-bearing one being:\n\n  BUG: KASAN: slab-use-after-free in __hlist_del include/linux/list.h:990 [inline]\n  BUG: KASAN: slab-use-after-free in hlist_del_rcu include/linux/rculist.h:516 [inline]\n  BUG: KASAN: slab-use-after-free in __xfrm_state_delete net/xfrm/xfrm_state.c\n  Write of size 8 at addr ffff8881198bcb70 by task kworker/u8:9/435\n\n  Workqueue: netns cleanup_net\n  Call Trace:\n   __hlist_del / hlist_del_rcu\n   __xfrm_state_delete\n   xfrm_state_delete\n   xfrm_state_flush\n   xfrm_state_fini\n   ops_exit_list\n   cleanup_net\n\nThe other observed signatures hit the same slab object from\n__xfrm_state_lookup, xfrm_alloc_spi, __xfrm_state_insert and an OOB\nwrite variant of __xfrm_state_delete, all on the byseq/byspi\nhash chains.\n\n__xfrm_state_delete() guards its byseq and byspi unhashes with\nvalue-based predicates:\n\n\tif (x-\u003ekm.seq)\n\t\thlist_del_rcu(\u0026x-\u003ebyseq);\n\tif (x-\u003eid.spi)\n\t\thlist_del_rcu(\u0026x-\u003ebyspi);\n\nwhile everywhere else in the file (e.g. state_cache, state_cache_input)\nthe safer hlist_unhashed() check is used. xfrm_alloc_spi() sets\nx-\u003eid.spi = newspi inside xfrm_state_lock and then immediately inserts\ninto byspi, but a path that observes x-\u003eid.spi != 0 outside of\nxfrm_state_lock can still skip-or-hit the byspi unhash inconsistently\nwith whether x is actually on the list. The same holds for x-\u003ekm.seq\nversus byseq, and the bydst/bysrc unhashes have no predicate at all,\nso a second __xfrm_state_delete() on the same object writes through\nLIST_POISON pprev.\n\nThe defensive change here:\n\n  - Use hlist_del_init_rcu() instead of hlist_del_rcu() on bydst,\n    bysrc, byseq and byspi so a second deletion is a no-op rather\n    than a write through LIST_POISON pprev. The byseq/byspi nodes\n    are already initialised in xfrm_state_alloc().\n  - Test hlist_unhashed() rather than the value predicate for\n    byseq/byspi, so the unhash decision tracks list state rather than\n    mutable scalar fields.\n\nEmpirical verification: applied this patch on top of v6.12.47, rebuilt,\nand re-ran the same syzkaller harness for 1h16m on a previously-crashy\nconfiguration that produced ~100 hits each of slab-use-after-free\nRead in xfrm_alloc_spi / Read in __xfrm_state_lookup / Write in\n__xfrm_state_delete. After the patch, 7.1M execs across 32 VMs at\n~1550 exec/sec produced zero xfrm_state UAF/OOB hits. /proc/slabinfo\nconfirms the xfrm_state slab is actively allocated and freed during\nthe run (~143 KiB resident), so the fuzzer is still exercising those\ncode paths -- they just no longer crash.\n\nReproduction:\n\n  - Linux 6.12.47 x86_64 + KASAN_GENERIC + KASAN_INLINE + KCOV\n  - syzkaller @ 746545b8b1e4c3a128db8652b340d3df90ce61db\n  - 32 QEMU/KVM VMs x 2 vCPU on AWS c5.metal bare metal\n  - 9 unique signatures collected in ~9h, all within xfrm_state\n    lifecycle","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":"xfrm: defensively unhash xfrm_state lists in __xfrm_state_delete","id":"CVE-2026-46116","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"use_after_free","year":"2026"},"n_packages":0,"n_references":8,"next":{"headline":"RDMA/mana: Remove user triggerable WARN_ON() in mana_ib_create_qp_rss()","id":"CVE-2026-46117"},"packages":[],"prev":{"headline":"block: add pgmap check to biovec_phys_mergeable","id":"CVE-2026-46115"},"products":["Linux"],"published":"2026-05-28","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":"total"},"state":"PUBLISHED","updated":"2026-10-19","vendors":["Linux"]},"summary":"A use-after-free vulnerability in the Linux kernel's xfrm subsystem allows attackers to cause denial of service or potentially execute code via crafted network namespace cleanup operations.","url":"https://insights.sbomify.com/CVE-2026-46116/"}