{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-72035", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-09T03:40:39.901Z", "datePublished": "2026-08-15T05:51:56.374Z", "dateUpdated": "2026-08-23T12:46:29.870Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-23T12:46:29.870Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: sch_taprio: Replace direct dequeue call with peek and qdisc_dequeue_peeked\n\nWhen taprio's software path peeks a non-work-conserving child qdisc, the\nchild stashes the peeked skb in its gso_skb; taprio_dequeue_from_txq()\nthen takes the packet with a direct child ->dequeue() call, which ignores\nthat stash, orphans the peeked skb and desyncs the child's qlen/backlog.\nWith a qfq child this re-enters the child on an emptied list and\ndereferences NULL, panicking the kernel from softirq on ordinary egress.\n\nTake the packet through qdisc_dequeue_peeked(), as sch_red and sch_sfb\nnow do. The helper returns the child's stashed skb first and is a no-op\nwhen there is none, so a work-conserving child is unaffected and the\ngated path now consumes the skb whose length was charged to the budget." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H", "baseScore": 8.2, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:N - The fault is in taprio's software egress dequeue path (`__dev_queue_xmit` → `__qdisc_run` → `taprio_dequeue` → `taprio_dequeue_from_txq`) during ordinary packet transmission in softirq; on TSN/automotive/industrial gateways where taprio+qfq is already deployed, any remote peer can trigger it by sending traffic that causes egress through the gated queues.\nAC:L - Once taprio is configured with a non-work-conserving child such as qfq on the software path (no full offload, TXTIME_ASSIST disabled), peek followed by the incorrect direct `dequeue()` deterministically orphans the stashed skb, desyncs qlen/backlog, and re-enters qfq on an emptied list; the attacker fully controls triggering traffic with no uncontrollable races.\nPR:N - Installing taprio and grafting a qfq child requires CAP_NET_ADMIN via RTM_NEWQDISC, but on reasonably deployed TSN/industrial systems where operators have already configured this stack, triggering the bug requires only the ability to send packets through the affected interface—no credentials or capabilities on the victim host.\nUI:N - Exploitation needs only attacker-generated network traffic (or any local sender) once the qdisc hierarchy exists; no victim login, mount, file open, or other interactive action is required at trigger time.\nS:U - The NULL dereference kernel panic and qdisc qlen/backlog corruption occur entirely within the host kernel's security authority; this is not a VM escape, container breakout, or IOMMU/DMA boundary bypass.\nC:N - The published failure mode is a NULL pointer dereference in qfq after taprio mishandles the peek stash; although the peeked skb is orphaned and child counters desync, there is no use-after-free, out-of-bounds read, or demonstrated arbitrary kernel memory disclosure primitive.\nI:L - Calling `child->ops->dequeue()` instead of `qdisc_dequeue_peeked()` orphans the peek-stashed skb and corrupts the child qdisc's qlen/backlog accounting before the fatal qfq re-entry, enabling attacker-driven mis-accounting of queued traffic on the affected egress path prior to panic.\nA:H - With a qfq child the desynchronized dequeue path dereferences NULL from softirq during ordinary egress, panicking the kernel; the condition is repeatable whenever gated transmission exercises the peek/dequeue mismatch, causing total host availability loss." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/sched/sch_taprio.c" ], "versions": [ { "version": "5a781ccbd19e4664babcbe4b4ead7aa2b9283d22", "lessThan": "51f8af240aed903e988755af33d7491030b50ae9", "status": "affected", "versionType": "git" }, { "version": "5a781ccbd19e4664babcbe4b4ead7aa2b9283d22", "lessThan": "17ab5f76f3899f67e5569722f334591f4b88b17b", "status": "affected", "versionType": "git" }, { "version": "5a781ccbd19e4664babcbe4b4ead7aa2b9283d22", "lessThan": "f60d5c12e0551012cee5c272b0bcbcc78f7bb506", "status": "affected", "versionType": "git" }, { "version": "5a781ccbd19e4664babcbe4b4ead7aa2b9283d22", "lessThan": "6ee5a7665a9080bcb05d703bf981a579436fd05e", "status": "affected", "versionType": "git" }, { "version": "5a781ccbd19e4664babcbe4b4ead7aa2b9283d22", "lessThan": "18d580cb00c55805633bae45e90cf22ed6b8e424", "status": "affected", "versionType": "git" }, { "version": "5a781ccbd19e4664babcbe4b4ead7aa2b9283d22", "lessThan": "e2b7ee61989f2d39df6c2cc06f9db1aea69bdb09", "status": "affected", "versionType": "git" }, { "version": "5a781ccbd19e4664babcbe4b4ead7aa2b9283d22", "lessThan": "2dcebbd1ad2e180fe7b98bf346ced69a872e11e6", "status": "affected", "versionType": "git" }, { "version": "5a781ccbd19e4664babcbe4b4ead7aa2b9283d22", "lessThan": "e056e1dfcddca877dd46d704e8ec9860cfc9ec44", "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_taprio.c" ], "versions": [ { "version": "4.20", "status": "affected" }, { "version": "0", "lessThan": "4.20", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.266", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.217", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.184", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.145", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.97", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.40", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.5", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2", "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": "4.20", "versionEndExcluding": "5.10.266" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.20", "versionEndExcluding": "5.15.217" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.20", "versionEndExcluding": "6.1.184" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.20", "versionEndExcluding": "6.6.145" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.20", "versionEndExcluding": "6.12.97" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.20", "versionEndExcluding": "6.18.40" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.20", "versionEndExcluding": "7.1.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.20", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/51f8af240aed903e988755af33d7491030b50ae9" }, { "url": "https://git.kernel.org/stable/c/17ab5f76f3899f67e5569722f334591f4b88b17b" }, { "url": "https://git.kernel.org/stable/c/f60d5c12e0551012cee5c272b0bcbcc78f7bb506" }, { "url": "https://git.kernel.org/stable/c/6ee5a7665a9080bcb05d703bf981a579436fd05e" }, { "url": "https://git.kernel.org/stable/c/18d580cb00c55805633bae45e90cf22ed6b8e424" }, { "url": "https://git.kernel.org/stable/c/e2b7ee61989f2d39df6c2cc06f9db1aea69bdb09" }, { "url": "https://git.kernel.org/stable/c/2dcebbd1ad2e180fe7b98bf346ced69a872e11e6" }, { "url": "https://git.kernel.org/stable/c/e056e1dfcddca877dd46d704e8ec9860cfc9ec44" } ], "title": "net/sched: sch_taprio: Replace direct dequeue call with peek and qdisc_dequeue_peeked", "x_generator": { "engine": "bippy-1.2.0" } } } }