CVE-2026-90075

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-90075", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.785Z", "datePublished": "2026-09-17T16:05:54.851Z", "dateUpdated": "2026-10-19T08:57:32.110Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T08:57:32.110Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: fq_codel: clamp default quantum and mtu\n\nfq_codel_init() sets q->quantum = psched_mtu(qdisc_dev(sch)) without\nclamping. A device with a huge MTU (e.g. dummy with max_mtu == 0\naccepting MTU 2147483634) makes psched_mtu() return 0x80000000, which\noverflows the signed flow->deficit to INT_MIN in fq_codel_dequeue(),\ncausing an infinite loop and soft lockup. Emulate fq_codel_change()\nand constrain to [256, FQ_CODEL_QUANTUM_MAX].\n\nThe same unclamped psched_mtu() is assigned to q->cparams.mtu a bit\nbelow, and fq_codel_change() never updates it. codel_should_drop()\ntests \"*backlog <= params->mtu\"; with mtu == 0x80000000 (~2 GiB) and\nthe default 32 MiB memory_limit, the test is always true, so CoDel is\nsilently and completely disabled (no drops, no ECN). Declare a single\nclamped mtu and assign both q->quantum and q->cparams.mtu from it,\nwhich also removes the double psched_mtu() call.\n\nConditions to recreate the bug: a device whose MTU (plus\nhard_header_len) wraps psched_mtu() into the sign bit (e.g. a dummy\ndevice with max_mtu == 0 accepting MTU 2147483634). Requires\nCAP_NET_ADMIN in a user namespace."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/sched/sch_fq_codel.c"], "versions": [{"version": "4b549a2ef4bef9965d97cbd992ba67930cd3e0fe", "lessThan": "d315ee8a07fd1810880227319cf60e6cd925ef22", "status": "affected", "versionType": "git"}, {"version": "4b549a2ef4bef9965d97cbd992ba67930cd3e0fe", "lessThan": "a9a5b2943a00df2ab81a2209f31dd9e87016f120", "status": "affected", "versionType": "git"}, {"version": "4b549a2ef4bef9965d97cbd992ba67930cd3e0fe", "lessThan": "3782067ec0d485628b6f1f9ede3eeeb4f611fcf2", "status": "affected", "versionType": "git"}, {"version": "4b549a2ef4bef9965d97cbd992ba67930cd3e0fe", "lessThan": "397e2b1f71d9f15b8b4e47d24eb620e4dff8878d", "status": "affected", "versionType": "git"}, {"version": "4b549a2ef4bef9965d97cbd992ba67930cd3e0fe", "lessThan": "324f86806673ae4a55f66d28db84577f46f615e1", "status": "affected", "versionType": "git"}, {"version": "4b549a2ef4bef9965d97cbd992ba67930cd3e0fe", "lessThan": "dfb4b61db886917244284b18b44b23d2254b82c2", "status": "affected", "versionType": "git"}, {"version": "4b549a2ef4bef9965d97cbd992ba67930cd3e0fe", "lessThan": "9f499e5827fdb6d7fdb46a7ce731852f6b1a1bb9", "status": "affected", "versionType": "git"}, {"version": "4b549a2ef4bef9965d97cbd992ba67930cd3e0fe", "lessThan": "d9ebd8f9aa8b2773235889cb903fafd61f2d8585", "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_fq_codel.c"], "versions": [{"version": "3.5", "status": "affected"}, {"version": "0", "lessThan": "3.5", "status": "unaffected", "versionType": "semver"}, {"version": "5.10.270", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.15.221", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.188", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.157", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.110", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.52", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.6", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.3", "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": "3.5", "versionEndExcluding": "5.10.270"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.5", "versionEndExcluding": "5.15.221"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.5", "versionEndExcluding": "6.1.188"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.5", "versionEndExcluding": "6.6.157"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.5", "versionEndExcluding": "6.12.110"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.5", "versionEndExcluding": "6.18.52"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.5", "versionEndExcluding": "7.2.6"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.5", "versionEndExcluding": "7.3"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/d315ee8a07fd1810880227319cf60e6cd925ef22"}, {"url": "https://git.kernel.org/stable/c/a9a5b2943a00df2ab81a2209f31dd9e87016f120"}, {"url": "https://git.kernel.org/stable/c/3782067ec0d485628b6f1f9ede3eeeb4f611fcf2"}, {"url": "https://git.kernel.org/stable/c/397e2b1f71d9f15b8b4e47d24eb620e4dff8878d"}, {"url": "https://git.kernel.org/stable/c/324f86806673ae4a55f66d28db84577f46f615e1"}, {"url": "https://git.kernel.org/stable/c/dfb4b61db886917244284b18b44b23d2254b82c2"}, {"url": "https://git.kernel.org/stable/c/9f499e5827fdb6d7fdb46a7ce731852f6b1a1bb9"}, {"url": "https://git.kernel.org/stable/c/d9ebd8f9aa8b2773235889cb903fafd61f2d8585"}], "title": "net/sched: fq_codel: clamp default quantum and mtu", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["net/sched/sch_fq_codel.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "d315ee8a07fd1810880227319cf60e6cd925ef22", "status": "affected", "version": "4b549a2ef4bef9965d97cbd992ba67930cd3e0fe", "versionType": "git"}, {"lessThan": "a9a5b2943a00df2ab81a2209f31dd9e87016f120", "status": "affected", "version": "4b549a2ef4bef9965d97cbd992ba67930cd3e0fe", "versionType": "git"}, {"lessThan": "3782067ec0d485628b6f1f9ede3eeeb4f611fcf2", "status": "affected", "version": "4b549a2ef4bef9965d97cbd992ba67930cd3e0fe", "versionType": "git"}, {"lessThan": "397e2b1f71d9f15b8b4e47d24eb620e4dff8878d", "status": "affected", "version": "4b549a2ef4bef9965d97cbd992ba67930cd3e0fe", "versionType": "git"}, {"lessThan": "324f86806673ae4a55f66d28db84577f46f615e1", "status": "affected", "version": "4b549a2ef4bef9965d97cbd992ba67930cd3e0fe", "versionType": "git"}, {"lessThan": "dfb4b61db886917244284b18b44b23d2254b82c2", "status": "affected", "version": "4b549a2ef4bef9965d97cbd992ba67930cd3e0fe", "versionType": "git"}, {"lessThan": "9f499e5827fdb6d7fdb46a7ce731852f6b1a1bb9", "status": "affected", "version": "4b549a2ef4bef9965d97cbd992ba67930cd3e0fe", "versionType": "git"}, {"lessThan": "d9ebd8f9aa8b2773235889cb903fafd61f2d8585", "status": "affected", "version": "4b549a2ef4bef9965d97cbd992ba67930cd3e0fe", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["net/sched/sch_fq_codel.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "3.5"}, {"lessThan": "3.5", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "5.10.*", "status": "unaffected", "version": "5.10.270", "versionType": "semver"}, {"lessThanOrEqual": "5.15.*", "status": "unaffected", "version": "5.15.221", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.188", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.157", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.110", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.52", "versionType": "semver"}, {"lessThanOrEqual": "7.2.*", "status": "unaffected", "version": "7.2.6", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.3", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: fq_codel: clamp default quantum and mtu\n\nfq_codel_init() sets q->quantum = psched_mtu(qdisc_dev(sch)) without\nclamping. A device with a huge MTU (e.g. dummy with max_mtu == 0\naccepting MTU 2147483634) makes psched_mtu() return 0x80000000, which\noverflows the signed flow->deficit to INT_MIN in fq_codel_dequeue(),\ncausing an infinite loop and soft lockup. Emulate fq_codel_change()\nand constrain to [256, FQ_CODEL_QUANTUM_MAX].\n\nThe same unclamped psched_mtu() is assigned to q->cparams.mtu a bit\nbelow, and fq_codel_change() never updates it. codel_should_drop()\ntests \"*backlog <= params->mtu\"; with mtu == 0x80000000 (~2 GiB) and\nthe default 32 MiB memory_limit, the test is always true, so CoDel is\nsilently and completely disabled (no drops, no ECN). Declare a single\nclamped mtu and assign both q->quantum and q->cparams.mtu from it,\nwhich also removes the double psched_mtu() call.\n\nConditions to recreate the bug: a device whose MTU (plus\nhard_header_len) wraps psched_mtu() into the sign bit (e.g. a dummy\ndevice with max_mtu == 0 accepting MTU 2147483634). Requires\nCAP_NET_ADMIN in a user namespace."}], "id": "CVE-2026-90075", "lastModified": "2026-10-19T09:18:56.300", "metrics": {}, "published": "2026-09-17T17:16:56.670", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/324f86806673ae4a55f66d28db84577f46f615e1"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/3782067ec0d485628b6f1f9ede3eeeb4f611fcf2"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/397e2b1f71d9f15b8b4e47d24eb620e4dff8878d"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/9f499e5827fdb6d7fdb46a7ce731852f6b1a1bb9"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/a9a5b2943a00df2ab81a2209f31dd9e87016f120"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/d315ee8a07fd1810880227319cf60e6cd925ef22"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/d9ebd8f9aa8b2773235889cb903fafd61f2d8585"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/dfb4b61db886917244284b18b44b23d2254b82c2"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[4b549a2ef4bef9965d97cbd992ba67930cd3e0fe,d315ee8a07fd1810880227319cf60e6cd925ef22)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[4b549a2ef4bef9965d97cbd992ba67930cd3e0fe,a9a5b2943a00df2ab81a2209f31dd9e87016f120)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[4b549a2ef4bef9965d97cbd992ba67930cd3e0fe,3782067ec0d485628b6f1f9ede3eeeb4f611fcf2)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[4b549a2ef4bef9965d97cbd992ba67930cd3e0fe,397e2b1f71d9f15b8b4e47d24eb620e4dff8878d)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[4b549a2ef4bef9965d97cbd992ba67930cd3e0fe,324f86806673ae4a55f66d28db84577f46f615e1)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[4b549a2ef4bef9965d97cbd992ba67930cd3e0fe,dfb4b61db886917244284b18b44b23d2254b82c2)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[4b549a2ef4bef9965d97cbd992ba67930cd3e0fe,9f499e5827fdb6d7fdb46a7ce731852f6b1a1bb9)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[4b549a2ef4bef9965d97cbd992ba67930cd3e0fe,d9ebd8f9aa8b2773235889cb903fafd61f2d8585)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[3.5,3.5]"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,3.5)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[5.10.270,5.11.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[5.15.221,5.16.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.1.188,6.2.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.6.157,6.7.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.110,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.52,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2.6,7.3.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.3-rc1,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-09-18T17:15:11.284434+00:00", "updated": "2026-09-20T04:30:18.060090+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"], "weaknesses": ["CWE-680", "CWE-704"]}