{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-53259 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-53259 is a high-severity use after free vulnerability in Linux kernel, published on 25 Jun 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-2026-53259 and fix it if it is affected.\n\nWhat it is: CVE-2026-53259 is a high-severity use after free vulnerability in Linux kernel, published on 25 Jun 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-2026-53259 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-2026-53259/ (Markdown: https://insights.sbomify.com/CVE-2026-53259/index.md)","id":"CVE-2026-53259","markdown":"https://insights.sbomify.com/CVE-2026-53259/index.md","name":"CVE-2026-53259","record":{"aliases":["BELL-CVE-2026-53259","DEBIAN-CVE-2026-53259","GHSA-hqjh-c323-5jv8","UBUNTU-CVE-2026-53259"],"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 race condition in the Linux kernel IPv6 anycast implementation allows a use-after-free, potentially leading to code execution or system crashes.","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-416","name":"Use After Free"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: anycast: insert aca into global hash under idev-\u003elock\n\nsyzbot reported a splat [1]: a slab-use-after-free in\nipv6_chk_acast_addr(), which walks the global inet6_acaddr_lst[] hash\nunder RCU and dereferences a struct ifacaddr6 that has already been\nfreed while still linked in the hash, so a later reader walks into a\ndangling node.\n\nIn __ipv6_dev_ac_inc() the aca is allocated with refcount 1, then\naca_get() bumps it to 2 to keep it alive across the unlocked region.\nIt is published to idev-\u003eac_list under idev-\u003elock, but\nipv6_add_acaddr_hash() runs after write_unlock_bh(). A concurrent\nteardown (ipv6_ac_destroy_dev() from addrconf_ifdown(), under RTNL)\ncan slip into that window:\n\n  CPU0 __ipv6_dev_ac_inc           CPU1 ipv6_ac_destroy_dev (RTNL)\n  ------------------------------   ------------------------------------\n  aca_alloc()              refcnt 1\n  aca_get()               refcnt 2\n  write_lock_bh(idev-\u003elock)\n    add aca to ac_list\n  write_unlock_bh(idev-\u003elock)\n                                   write_lock_bh(idev-\u003elock)\n                                     pull aca off ac_list\n                                   write_unlock_bh(idev-\u003elock)\n                                   ipv6_del_acaddr_hash(aca)\n                                     hlist_del_init_rcu() is a no-op,\n                                     aca is not in the hash yet\n                                   aca_put()           refcnt 2-\u003e1\n  ipv6_add_acaddr_hash(aca)\n    aca now inserted into the hash\n  aca_put()                refcnt 1-\u003e0\n    call_rcu(aca_free_rcu) -\u003e kfree(aca)\n\nThe hash removal becomes a no-op because the insertion has not\nhappened yet, so once CPU0 inserts and drops the last reference, the\naca is freed while still linked in inet6_acaddr_lst[], and readers\ndereference freed memory after the slab slot is reused.\n\nThis window opened once RTNL stopped serializing the join path against\ndevice teardown. Move ipv6_add_acaddr_hash() inside the idev-\u003elock\nsection so the ac_list and hash insertions are atomic with respect to\nteardown: a racing remover now either misses the aca entirely or finds\nit in both lists.\n\nacaddr_hash_lock is now nested under idev-\u003elock, which is acquired in\nsoftirq context, so switch all acaddr_hash_lock sites to spin_lock_bh()\nto avoid the irq lock inversion reported in [2].\n\n[1] https://syzkaller.appspot.com/bug?extid=a01df04303c131efbf3a\n[2] https://lore.kernel.org/netdev/6a194ef7.ba3b1513.1890b4.0000.GAE@google.com/","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":"ipv6: anycast: insert aca into global hash under idev-\u003elock","id":"CVE-2026-53259","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":3,"next":{"headline":"tcp: Add preempt_{disable,enable}_nested() in reqsk_queue_hash_req().","id":"CVE-2026-53260"},"packages":[],"prev":{"headline":"wifi: fix leak if split 6 GHz scanning fails","id":"CVE-2026-53258"},"products":["Linux"],"published":"2026-06-25","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":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-08-05","vendors":["Linux"]},"summary":"A race condition in the Linux kernel IPv6 anycast implementation allows a use-after-free, potentially leading to code execution or system crashes.","url":"https://insights.sbomify.com/CVE-2026-53259/"}