{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-38083","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2025-04-16T04:51:23.981Z","datePublished":"2025-06-20T11:21:51.554Z","dateUpdated":"2026-08-05T11:59:21.321Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T11:59:21.321Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet_sched: prio: fix a race in prio_tune()\n\nGerrard Tai reported a race condition in PRIO, whenever SFQ perturb timer\nfires at the wrong time.\n\nThe race is as follows:\n\nCPU 0                                 CPU 1\n[1]: lock root\n[2]: qdisc_tree_flush_backlog()\n[3]: unlock root\n |\n |                                    [5]: lock root\n |                                    [6]: rehash\n |                                    [7]: qdisc_tree_reduce_backlog()\n |\n[4]: qdisc_put()\n\nThis can be abused to underflow a parent's qlen.\n\nCalling qdisc_purge_queue() instead of qdisc_tree_flush_backlog()\nshould fix the race, because all packets will be purged from the qdisc\nbefore releasing the lock."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The vulnerable code is reached only via `RTM_NEWQDISC` netlink messages (`tc qdisc change ... prio bands N`) combined with locally enqueued traffic; no data from a remote peer reaches `prio_tune()`.\nAC:L - The attacker controls both sides of the race — they set the SFQ child's `perturb` period and drop-forcing `flows`/`depth` parameters, choose when to issue the band-shrinking change, and can retry unboundedly until the timer lands in the unlocked window between `sch_tree_unlock()` and `qdisc_put()`.\nPR:L - The tc/qdisc netlink path is gated only by `netlink_net_capable(skb, CAP_NET_ADMIN)` against the netns' own user namespace, so an unprivileged user obtains it with `unshare -Urn` and can also autoload `sch_prio`/`sch_sfq` from that context.\nUI:N - The attacker performs every step themselves — building the prio/SFQ hierarchy, generating the traffic, and triggering the reconfiguration. No victim action is involved.\nS:U - The corrupted `qlen`/`backlog` accounting and any resulting memory corruption stay within the kernel's own security authority; this is standard local kernel privilege escalation with no VM, IOMMU, or sandbox boundary crossed.\nC:H - The double subtraction underflows the unsigned `q.qlen`, desynchronizing the qdisc tree so classes stay on parent active lists after their child qdiscs are freed, yielding a use-after-free on `struct Qdisc`/class objects that can be groomed into an arbitrary kernel-memory read.\nI:H - The same qlen-desync-to-UAF primitive gives control over reallocated heap objects and their function pointers and list heads, enabling arbitrary write and control-flow hijacking — the well-known net/sched local privilege escalation pattern.\nA:H - Even unweaponized, the underflowed `qlen` makes an empty qdisc appear to hold ~4 billion packets, causing dequeue-from-empty warnings, stalled transmit paths, and use-after-free oopses that panic the kernel."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/sched/sch_prio.c"],"versions":[{"version":"7b8e0b6e659983154c8d7e756cdb833d89a3d4d7","lessThan":"53d11560e957d53ee87a0653d258038ce12361b7","status":"affected","versionType":"git"},{"version":"7b8e0b6e659983154c8d7e756cdb833d89a3d4d7","lessThan":"4483d8b9127591c60c4eb789d6cab953bc4522a9","status":"affected","versionType":"git"},{"version":"7b8e0b6e659983154c8d7e756cdb833d89a3d4d7","lessThan":"20f68e6a9e41693cb0e55e5b9ebbcb40983a4b8f","status":"affected","versionType":"git"},{"version":"7b8e0b6e659983154c8d7e756cdb833d89a3d4d7","lessThan":"3aaa7c01cf19d9b9bb64b88b65c3a6fd05da2eb4","status":"affected","versionType":"git"},{"version":"7b8e0b6e659983154c8d7e756cdb833d89a3d4d7","lessThan":"46c15c9d0f65c9ba857d63f53264f4b17e8a715f","status":"affected","versionType":"git"},{"version":"7b8e0b6e659983154c8d7e756cdb833d89a3d4d7","lessThan":"e3f6745006dc9423d2b065b90f191cfa11b1b584","status":"affected","versionType":"git"},{"version":"7b8e0b6e659983154c8d7e756cdb833d89a3d4d7","lessThan":"93f9eeb678d4c9c1abf720b3615fa8299a490845","status":"affected","versionType":"git"},{"version":"7b8e0b6e659983154c8d7e756cdb833d89a3d4d7","lessThan":"d35acc1be3480505b5931f17e4ea9b7617fea4d3","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_prio.c"],"versions":[{"version":"5.0","status":"affected"},{"version":"0","lessThan":"5.0","status":"unaffected","versionType":"semver"},{"version":"5.4.295","lessThanOrEqual":"5.4.*","status":"unaffected","versionType":"semver"},{"version":"5.10.239","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.186","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.142","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.94","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.34","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.15.3","lessThanOrEqual":"6.15.*","status":"unaffected","versionType":"semver"},{"version":"6.16","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":"5.0","versionEndExcluding":"5.4.295"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.0","versionEndExcluding":"5.10.239"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.0","versionEndExcluding":"5.15.186"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.0","versionEndExcluding":"6.1.142"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.0","versionEndExcluding":"6.6.94"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.0","versionEndExcluding":"6.12.34"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.0","versionEndExcluding":"6.15.3"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.0","versionEndExcluding":"6.16"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/53d11560e957d53ee87a0653d258038ce12361b7"},{"url":"https://git.kernel.org/stable/c/4483d8b9127591c60c4eb789d6cab953bc4522a9"},{"url":"https://git.kernel.org/stable/c/20f68e6a9e41693cb0e55e5b9ebbcb40983a4b8f"},{"url":"https://git.kernel.org/stable/c/3aaa7c01cf19d9b9bb64b88b65c3a6fd05da2eb4"},{"url":"https://git.kernel.org/stable/c/46c15c9d0f65c9ba857d63f53264f4b17e8a715f"},{"url":"https://git.kernel.org/stable/c/e3f6745006dc9423d2b065b90f191cfa11b1b584"},{"url":"https://git.kernel.org/stable/c/93f9eeb678d4c9c1abf720b3615fa8299a490845"},{"url":"https://git.kernel.org/stable/c/d35acc1be3480505b5931f17e4ea9b7617fea4d3"}],"title":"net_sched: prio: fix a race in prio_tune()","x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CVE Program Container","references":[{"url":"https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html"},{"url":"https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html"}],"providerMetadata":{"orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE","dateUpdated":"2025-11-03T17:33:50.557Z"}},{"x_adpType":"supplier","providerMetadata":{"orgId":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e","shortName":"siemens-SADP","dateUpdated":"2026-07-14T12:41:26.853Z"},"affected":[{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518-4 PN/DP MFP","versions":[{"status":"affected","version":"V3.1.5","lessThan":"*","versionType":"custom"}],"defaultStatus":"unknown"},{"vendor":"Siemens","product":"SIMATIC S7-1500 CPU 1518-4 PN/DP MFP","versions":[{"status":"affected","version":"V3.1.5","lessThan":"*","versionType":"custom"}],"defaultStatus":"unknown"},{"vendor":"Siemens","product":"SIMATIC 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