{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-43496 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-43496 is a medium-severity vulnerability in Linux kernel, published on 21 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-2026-43496 and fix it if it is affected.\n\nWhat it is: CVE-2026-43496 is a medium-severity vulnerability in Linux kernel, published on 21 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-2026-43496 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-2026-43496/ (Markdown: https://insights.sbomify.com/CVE-2026-43496/index.md)","id":"CVE-2026-43496","markdown":"https://insights.sbomify.com/CVE-2026-43496/index.md","name":"CVE-2026-43496","record":{"aliases":["AZL-87081","BELL-CVE-2026-43496","DEBIAN-CVE-2026-43496","GHSA-86mq-wj5h-4fr6","ROOT-OS-DEBIAN-11-CVE-2026-43496","ROOT-OS-DEBIAN-12-CVE-2026-43496","ROOT-OS-UBUNTU-2204-CVE-2026-43496","ROOT-OS-UBUNTU-2404-CVE-2026-43496","UBUNTU-CVE-2026-43496"],"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":"low_privilege","summary":"A null pointer dereference in the Linux kernel's RED qdisc can cause a kernel panic when specific child qdiscs are used.","user_interaction":"not_required","vuln_class":"null_dereference"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[{"product":"linux_kernel","vendor":"linux"}],"cvss":{"score":5.5,"severity":"medium","source":"nvd","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[{"id":"CWE-476","name":"NULL Pointer Dereference"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: sch_red: Replace direct dequeue call with peek and qdisc_dequeue_peeked\n\nWhen red qdisc has children (eg qfq qdisc) whose peek() callback is\nqdisc_peek_dequeued(), we could get a kernel panic. When the parent of such\nqdiscs (eg illustrated in patch #3 as tbf) wants to retrieve an skb from\nits child (red in this case), it will do the following:\n 1a. do a peek() - and when sensing there's an skb the child can offer, then\n     - the child in this case(red) calls its child's (qfq) peek.\n        qfq does the right thing and will return the gso_skb queue packet.\n        Note: if there wasnt a gso_skb entry then qfq will store it there.\n 1b. invoke a dequeue() on the child (red). And herein lies the problem.\n     - red will call the child's dequeue() which will essentially just\n       try to grab something of qfq's queue.\n\n[   78.667668][  T363] KASAN: null-ptr-deref in range [0x0000000000000048-0x000000000000004f]\n[   78.667927][  T363] CPU: 1 UID: 0 PID: 363 Comm: ping Not tainted 7.1.0-rc1-00033-g46f74a3f7d57-dirty #790 PREEMPT(full)\n[   78.668263][  T363] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011\n[   78.668486][  T363] RIP: 0010:qfq_dequeue+0x446/0xc90 [sch_qfq]\n[   78.668718][  T363] Code: 54 c0 e8 dd 90 00 f1 48 c7 c7 e0 03 54 c0 48 89 de e8 ce 90 00 f1 48 8d 7b 48 b8 ff ff 37 00 48 89 fa 48 c1 e0 2a 48 c1 ea 03 \u003c80\u003e 3c 02 00 74 05 e8 ef a1 e1 f1 48 8b 7b 48 48 8d 54 24 58 48 8d\n[   78.669312][  T363] RSP: 0018:ffff88810de573e0 EFLAGS: 00010216\n[   78.669533][  T363] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000\n[   78.669790][  T363] RDX: 0000000000000009 RSI: 0000000000000004 RDI: 0000000000000048\n[   78.670044][  T363] RBP: ffff888110dc4000 R08: ffffffffb1b0885a R09: fffffbfff6ba9078\n[   78.670297][  T363] R10: 0000000000000003 R11: ffff888110e31c80 R12: 0000001880000000\n[   78.670560][  T363] R13: ffff888110dc4150 R14: ffff888110dc42b8 R15: 0000000000000200\n[   78.670814][  T363] FS:  00007f66a8f09c40(0000) GS:ffff888163428000(0000) knlGS:0000000000000000\n[   78.671110][  T363] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[   78.671324][  T363] CR2: 000055db4c6a30a8 CR3: 000000010da67000 CR4: 0000000000750ef0\n[   78.671585][  T363] PKRU: 55555554\n[   78.671713][  T363] Call Trace:\n[   78.671843][  T363]  \u003cTASK\u003e\n[   78.671936][  T363]  ? __pfx_qfq_dequeue+0x10/0x10 [sch_qfq]\n[   78.672148][  T363]  ? __pfx__printk+0x10/0x10\n[   78.672322][  T363]  ? srso_alias_return_thunk+0x5/0xfbef5\n[   78.672496][  T363]  ? lockdep_hardirqs_on_prepare+0xa8/0x1a0\n[   78.672706][  T363]  ? srso_alias_return_thunk+0x5/0xfbef5\n[   78.672875][  T363]  ? trace_hardirqs_on+0x19/0x1a0\n[   78.673047][  T363]  red_dequeue+0x65/0x270 [sch_red]\n[   78.673217][  T363]  ? srso_alias_return_thunk+0x5/0xfbef5\n[   78.673385][  T363]  tbf_dequeue.cold+0xb0/0x70c [sch_tbf]\n[   78.673566][  T363]  __qdisc_run+0x169/0x1900\n\nThe right thing to do in #1b is to grab the skb off gso_skb queue.\nThis patchset fixes that issue by changing #1b to use qdisc_dequeue_peeked()\nmethod instead.","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/sched: sch_red: Replace direct dequeue call with peek and qdisc_dequeue_peeked","id":"CVE-2026-43496","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"null_dereference","year":"2026"},"n_packages":0,"n_references":8,"next":{"headline":"fbdev: udlfb: add vm_ops to dlfb_ops_mmap to prevent use-after-free","id":"CVE-2026-43497"},"packages":[],"prev":{"headline":"net: wwan: t7xx: validate port_count against message length in t7xx_port_enum_msg_handler","id":"CVE-2026-43495"},"products":["Linux"],"published":"2026-05-21","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":"2026-10-15","vendors":["Linux"]},"summary":"A null pointer dereference in the Linux kernel's RED qdisc can cause a kernel panic when specific child qdiscs are used.","url":"https://insights.sbomify.com/CVE-2026-43496/"}