CVE-2026-43496

{"id": "CVE-2026-43496", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.5, "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 1.8}]}, "affected": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "affectedData": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "77be155cba4e163e8bba9fd27222a8b6189ec4f7", "lessThan": "03b0aaeba082ae981a0dfe96cdd03d02050537a1", "versionType": "git"}, {"status": "affected", "version": "77be155cba4e163e8bba9fd27222a8b6189ec4f7", "lessThan": "c7335f4dc0fa21f7015b910c6fc2f4d599732328", "versionType": "git"}, {"status": "affected", "version": "77be155cba4e163e8bba9fd27222a8b6189ec4f7", "lessThan": "45cd83c5c470ba49fe261489c8358ad7b9df7c45", "versionType": "git"}, {"status": "affected", "version": "77be155cba4e163e8bba9fd27222a8b6189ec4f7", "lessThan": "36aa34f42cb6842cf371f3a2d3e855d24fd57a50", "versionType": "git"}, {"status": "affected", "version": "77be155cba4e163e8bba9fd27222a8b6189ec4f7", "lessThan": "ce051eede433f876d322ac3550a36a3c6fc4c231", "versionType": "git"}, {"status": "affected", "version": "77be155cba4e163e8bba9fd27222a8b6189ec4f7", "lessThan": "8d09618840b99ef00154d3e731ce9b11e096196d", "versionType": "git"}, {"status": "affected", "version": "77be155cba4e163e8bba9fd27222a8b6189ec4f7", "lessThan": "587dcf970a525f543d8b5855d9f37a4ca97b76ef", "versionType": "git"}, {"status": "affected", "version": "77be155cba4e163e8bba9fd27222a8b6189ec4f7", "lessThan": "458d5615272d3de535748342eb68ca492343048c", "versionType": "git"}], "programFiles": ["net/sched/sch_red.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "2.6.29"}, {"status": "unaffected", "version": "0", "lessThan": "2.6.29", "versionType": "semver"}, {"status": "unaffected", "version": "5.10.258", "versionType": "semver", "lessThanOrEqual": "5.10.*"}, {"status": "unaffected", "version": "5.15.209", "versionType": "semver", "lessThanOrEqual": "5.15.*"}, {"status": "unaffected", "version": "6.1.175", "versionType": "semver", "lessThanOrEqual": "6.1.*"}, {"status": "unaffected", "version": "6.6.140", "versionType": "semver", "lessThanOrEqual": "6.6.*"}, {"status": "unaffected", "version": "6.12.88", "versionType": "semver", "lessThanOrEqual": "6.12.*"}, {"status": "unaffected", "version": "6.18.30", "versionType": "semver", "lessThanOrEqual": "6.18.*"}, {"status": "unaffected", "version": "7.0.7", "versionType": "semver", "lessThanOrEqual": "7.0.*"}, {"status": "unaffected", "version": "7.1", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["net/sched/sch_red.c"], "defaultStatus": "affected"}]}], "published": "2026-05-21T13:16:18.960", "references": [{"url": "https://git.kernel.org/stable/c/03b0aaeba082ae981a0dfe96cdd03d02050537a1", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/36aa34f42cb6842cf371f3a2d3e855d24fd57a50", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/458d5615272d3de535748342eb68ca492343048c", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/45cd83c5c470ba49fe261489c8358ad7b9df7c45", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/587dcf970a525f543d8b5855d9f37a4ca97b76ef", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/8d09618840b99ef00154d3e731ce9b11e096196d", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/c7335f4dc0fa21f7015b910c6fc2f4d599732328", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/ce051eede433f876d322ac3550a36a3c6fc4c231", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-476"}]}], "descriptions": [{"lang": "en", "value": "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 <80> 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] <TASK>\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."}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nnet/sched: sch_red: Reemplazar la llamada directa a dequeue con peek y qdisc_dequeue_peeked\n\nCuando red qdisc tiene hijos (por ejemplo, qfq qdisc) cuya funci\u00f3n de devoluci\u00f3n de llamada peek() es qdisc_peek_dequeued(), podr\u00edamos obtener un p\u00e1nico del kernel. Cuando el padre de tales qdiscs (por ejemplo, ilustrado en el parche #3 como tbf) quiere recuperar un skb de su hijo (red en este caso), har\u00e1 lo siguiente:\n 1a. hacer un peek() - y al detectar que hay un skb que el hijo puede ofrecer, entonces\n - el hijo en este caso (red) llama al peek de su hijo (qfq).\n qfq hace lo correcto y devolver\u00e1 el paquete de la cola gso_skb.\n Nota: si no hubiera una entrada gso_skb, entonces qfq lo almacenar\u00e1 all\u00ed.\n 1b. invocar un dequeue() en el hijo (red). Y aqu\u00ed radica el problema.\n - red llamar\u00e1 al dequeue() del hijo, que esencialmente solo intentar\u00e1 tomar algo de la cola de qfq.\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 <80> 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] <TASK>\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\nLo correcto a hacer en #1b es tomar el skb de la cola gso_skb.\nEste conjunto de parches soluciona ese problema cambiando #1b para usar el m\u00e9todo qdisc_dequeue_peeked() en su lugar."}], "lastModified": "2026-07-23T16:10:00.137", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "CE62A641-B2AF-4077-9B44-DCE56A381D1C", "versionEndExcluding": "5.10.258", "versionStartIncluding": "2.6.29"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "919C10A9-7951-4A74-BADD-C135A0A8D8B4", "versionEndExcluding": "5.15.209", "versionStartIncluding": "5.11"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "92385813-D91D-480D-83A1-F423D2CBB2BA", "versionEndExcluding": "6.1.175", "versionStartIncluding": "5.16"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "A1A92866-F406-43B5-B2D1-CFC274753E9D", "versionEndExcluding": "6.6.140", "versionStartIncluding": "6.2"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "5AFBE0EC-CCDF-4207-AE92-ABF958125CA4", "versionEndExcluding": "6.12.88", "versionStartIncluding": "6.7"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "BF39AE08-AE6D-4410-8FBE-76F6BF5BF55B", "versionEndExcluding": "6.18.30", "versionStartIncluding": "6.13"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "D0893CA7-9AE6-4DFE-AC75-48967D73AD8E", "versionEndExcluding": "7.0.7", "versionStartIncluding": "6.19"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "B1EF7059-E670-45F4-B422-54C40FA86390"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "0D38F0BF-A728-4133-A358-D44A2F7EE6D6"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}