{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-43249 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-43249 is a high-severity use after free vulnerability in Linux kernel, published on 6 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-2026-43249 and fix it if it is affected.\n\nWhat it is: CVE-2026-43249 is a high-severity use after free vulnerability in Linux kernel, published on 6 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-2026-43249 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-2026-43249/ (Markdown: https://insights.sbomify.com/CVE-2026-43249/index.md)","id":"CVE-2026-43249","markdown":"https://insights.sbomify.com/CVE-2026-43249/index.md","name":"CVE-2026-43249","record":{"aliases":["AZL-86390","BELL-CVE-2026-43249","DEBIAN-CVE-2026-43249","GHSA-387w-9mx8-66cc","ROOT-OS-DEBIAN-11-CVE-2026-43249","ROOT-OS-DEBIAN-12-CVE-2026-43249","ROOT-OS-UBUNTU-2204-CVE-2026-43249","ROOT-OS-UBUNTU-2404-CVE-2026-43249","UBUNTU-CVE-2026-43249"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel","requires_auth":"none","summary":"A race condition in the Linux kernel's 9p/xen driver allows a double-free, leading to a general protection fault and system crash.","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":8.8,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"cwes":[{"id":"CWE-415","name":"Double Free"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\n9p/xen: protect xen_9pfs_front_free against concurrent calls\n\nThe xenwatch thread can race with other back-end change notifications\nand call xen_9pfs_front_free() twice, hitting the observed general\nprotection fault due to a double-free. Guard the teardown path so only\none caller can release the front-end state at a time, preventing the\ncrash.\n\nThis is a fix for the following double-free:\n\n[   27.052347] Oops: general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6b6b: 0000 [#1] SMP DEBUG_PAGEALLOC NOPTI\n[   27.052357] CPU: 0 UID: 0 PID: 32 Comm: xenwatch Not tainted 6.18.0-02087-g51ab33fc0a8b-dirty #60 PREEMPT(none)\n[   27.052363] RIP: e030:xen_9pfs_front_free+0x1d/0x150\n[   27.052368] Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 41 55 41 54 55 48 89 fd 48 c7 c7 48 d0 92 85 53 e8 cb cb 05 00 48 8b 45 08 48 8b 55 00 \u003c48\u003e 3b 28 0f 85 f9 28 35 fe 48 3b 6a 08 0f 85 ef 28 35 fe 48 89 42\n[   27.052377] RSP: e02b:ffffc9004016fdd0 EFLAGS: 00010246\n[   27.052381] RAX: 6b6b6b6b6b6b6b6b RBX: ffff88800d66e400 RCX: 0000000000000000\n[   27.052385] RDX: 6b6b6b6b6b6b6b6b RSI: 0000000000000000 RDI: 0000000000000000\n[   27.052389] RBP: ffff88800a887040 R08: 0000000000000000 R09: 0000000000000000\n[   27.052393] R10: 0000000000000000 R11: 0000000000000000 R12: ffff888009e46b68\n[   27.052397] R13: 0000000000000200 R14: 0000000000000000 R15: ffff88800a887040\n[   27.052404] FS:  0000000000000000(0000) GS:ffff88808ca57000(0000) knlGS:0000000000000000\n[   27.052408] CS:  e030 DS: 0000 ES: 0000 CR0: 0000000080050033\n[   27.052412] CR2: 00007f9714004360 CR3: 0000000004834000 CR4: 0000000000050660\n[   27.052418] Call Trace:\n[   27.052420]  \u003cTASK\u003e\n[   27.052422]  xen_9pfs_front_changed+0x5d5/0x720\n[   27.052426]  ? xenbus_otherend_changed+0x72/0x140\n[   27.052430]  ? __pfx_xenwatch_thread+0x10/0x10\n[   27.052434]  xenwatch_thread+0x94/0x1c0\n[   27.052438]  ? __pfx_autoremove_wake_function+0x10/0x10\n[   27.052442]  kthread+0xf8/0x240\n[   27.052445]  ? __pfx_kthread+0x10/0x10\n[   27.052449]  ? __pfx_kthread+0x10/0x10\n[   27.052452]  ret_from_fork+0x16b/0x1a0\n[   27.052456]  ? __pfx_kthread+0x10/0x10\n[   27.052459]  ret_from_fork_asm+0x1a/0x30\n[   27.052463]  \u003c/TASK\u003e\n[   27.052465] Modules linked in:\n[   27.052471] ---[ end trace 0000000000000000 ]---","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":"9p/xen: protect xen_9pfs_front_free against concurrent calls","id":"CVE-2026-43249","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":5,"next":{"headline":"usb: chipidea: udc: fix DMA and SG cleanup in _ep_nuke()","id":"CVE-2026-43250"},"packages":[],"prev":{"headline":"vhost: move vdpa group bound check to vhost_vdpa","id":"CVE-2026-43248"},"products":["Linux"],"published":"2026-05-06","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":"2026-10-21","vendors":["Linux"]},"summary":"A race condition in the Linux kernel's 9p/xen driver allows a double-free, leading to a general protection fault and system crash.","url":"https://insights.sbomify.com/CVE-2026-43249/"}