{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-43496", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-05-01T14:12:56.013Z", "datePublished": "2026-05-21T12:12:46.584Z", "dateUpdated": "2026-06-14T17:45:26.779Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-06-14T17:45:26.779Z" }, "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] \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." } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/sched/sch_red.c" ], "versions": [ { "version": "77be155cba4e163e8bba9fd27222a8b6189ec4f7", "lessThan": "03b0aaeba082ae981a0dfe96cdd03d02050537a1", "status": "affected", "versionType": "git" }, { "version": "77be155cba4e163e8bba9fd27222a8b6189ec4f7", "lessThan": "c7335f4dc0fa21f7015b910c6fc2f4d599732328", "status": "affected", "versionType": "git" }, { "version": "77be155cba4e163e8bba9fd27222a8b6189ec4f7", "lessThan": "45cd83c5c470ba49fe261489c8358ad7b9df7c45", "status": "affected", "versionType": "git" }, { "version": "77be155cba4e163e8bba9fd27222a8b6189ec4f7", "lessThan": "36aa34f42cb6842cf371f3a2d3e855d24fd57a50", "status": "affected", "versionType": "git" }, { "version": "77be155cba4e163e8bba9fd27222a8b6189ec4f7", "lessThan": "ce051eede433f876d322ac3550a36a3c6fc4c231", "status": "affected", "versionType": "git" }, { "version": "77be155cba4e163e8bba9fd27222a8b6189ec4f7", "lessThan": "8d09618840b99ef00154d3e731ce9b11e096196d", "status": "affected", "versionType": "git" }, { "version": "77be155cba4e163e8bba9fd27222a8b6189ec4f7", "lessThan": "587dcf970a525f543d8b5855d9f37a4ca97b76ef", "status": "affected", "versionType": "git" }, { "version": "77be155cba4e163e8bba9fd27222a8b6189ec4f7", "lessThan": "458d5615272d3de535748342eb68ca492343048c", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/sched/sch_red.c" ], "versions": [ { "version": "2.6.29", "status": "affected" }, { "version": "0", "lessThan": "2.6.29", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.258", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.209", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.175", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.140", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.88", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.30", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0.7", "lessThanOrEqual": "7.0.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.29", "versionEndExcluding": "5.10.258" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.29", "versionEndExcluding": "5.15.209" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.29", "versionEndExcluding": "6.1.175" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.29", "versionEndExcluding": "6.6.140" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.29", "versionEndExcluding": "6.12.88" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.29", "versionEndExcluding": "6.18.30" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.29", "versionEndExcluding": "7.0.7" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.29", "versionEndExcluding": "7.1" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/03b0aaeba082ae981a0dfe96cdd03d02050537a1" }, { "url": "https://git.kernel.org/stable/c/c7335f4dc0fa21f7015b910c6fc2f4d599732328" }, { "url": "https://git.kernel.org/stable/c/45cd83c5c470ba49fe261489c8358ad7b9df7c45" }, { "url": "https://git.kernel.org/stable/c/36aa34f42cb6842cf371f3a2d3e855d24fd57a50" }, { "url": "https://git.kernel.org/stable/c/ce051eede433f876d322ac3550a36a3c6fc4c231" }, { "url": "https://git.kernel.org/stable/c/8d09618840b99ef00154d3e731ce9b11e096196d" }, { "url": "https://git.kernel.org/stable/c/587dcf970a525f543d8b5855d9f37a4ca97b76ef" }, { "url": "https://git.kernel.org/stable/c/458d5615272d3de535748342eb68ca492343048c" } ], "title": "net/sched: sch_red: Replace direct dequeue call with peek and qdisc_dequeue_peeked", "x_generator": { "engine": "bippy-1.2.0" } } } }