{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2025-37953",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2025-04-16T04:51:23.973Z",
        "datePublished": "2025-05-20T16:01:47.818Z",
        "dateUpdated": "2026-05-11T21:18:17.815Z"
    },
    "containers": {
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                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-05-11T21:18:17.815Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsch_htb: make htb_deactivate() idempotent\n\nAlan reported a NULL pointer dereference in htb_next_rb_node()\nafter we made htb_qlen_notify() idempotent.\n\nIt turns out in the following case it introduced some regression:\n\nhtb_dequeue_tree():\n  |-> fq_codel_dequeue()\n    |-> qdisc_tree_reduce_backlog()\n      |-> htb_qlen_notify()\n        |-> htb_deactivate()\n  |-> htb_next_rb_node()\n  |-> htb_deactivate()\n\nFor htb_next_rb_node(), after calling the 1st htb_deactivate(), the\nclprio[prio]->ptr could be already set to  NULL, which means\nhtb_next_rb_node() is vulnerable here.\n\nFor htb_deactivate(), although we checked qlen before calling it, in\ncase of qlen==0 after qdisc_tree_reduce_backlog(), we may call it again\nwhich triggers the warning inside.\n\nTo fix the issues here, we need to:\n\n1) Make htb_deactivate() idempotent, that is, simply return if we\n   already call it before.\n2) Make htb_next_rb_node() safe against ptr==NULL.\n\nMany thanks to Alan for testing and for the reproducer."
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "net/sched/sch_htb.c"
                    ],
                    "versions": [
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                            "version": "e6b45f4de763b00dc1c55e685e2dd1aaf525d3c1",
                            "lessThan": "99ff8a20fd61315bf9ae627440a5ff07d22ee153",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "32ae12ce6a9f6bace186ca7335220ff59b6cc3cd",
                            "lessThan": "a9945f7cf1709adc5d2d31cb6cfc85627ce299a8",
                            "status": "affected",
                            "versionType": "git"
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                        {
                            "version": "967955c9e57f8eebfccc298037d4aaf3d42bc1c9",
                            "lessThan": "c2d25fddd867ce20a266806634eeeb5c30cb520c",
                            "status": "affected",
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                            "version": "73cf6af13153d62f9b76eff422eea79dbc70f15e",
                            "lessThan": "c928dd4f6bf0c25c72b11824a1e9ac9bd37296a0",
                            "status": "affected",
                            "versionType": "git"
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                        {
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                            "lessThan": "31ff70ad39485698cf779f2078132d80b57f6c07",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "0a188c0e197383683fd093ab1ea6ce9a5869a6ea",
                            "lessThan": "98cd7ed92753090a714f0802d4434314526fe61d",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "a61f1b5921761fbaf166231418bc1db301e5bf59",
                            "lessThan": "c4792b9e38d2f61b07eac72f10909fa76130314b",
                            "status": "affected",
                            "versionType": "git"
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                            "lessThan": "3769478610135e82b262640252d90f6efb05be71",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "net/sched/sch_htb.c"
                    ],
                    "versions": [
                        {
                            "version": "6.1.138",
                            "lessThan": "6.1.139",
                            "status": "affected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.6.90",
                            "lessThan": "6.6.91",
                            "status": "affected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.28",
                            "lessThan": "6.12.29",
                            "status": "affected",
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                        {
                            "version": "6.14.6",
                            "lessThan": "6.14.7",
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                            "versionType": "semver"
                        }
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            "cpeApplicability": [
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                    "nodes": [
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                            "operator": "OR",
                            "negate": false,
                            "cpeMatch": [
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                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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                                },
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            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/99ff8a20fd61315bf9ae627440a5ff07d22ee153"
                },
                {
                    "url": "https://git.kernel.org/stable/c/a9945f7cf1709adc5d2d31cb6cfc85627ce299a8"
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                },
                {
                    "url": "https://git.kernel.org/stable/c/3769478610135e82b262640252d90f6efb05be71"
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            ],
            "title": "sch_htb: make htb_deactivate() idempotent",
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        "adp": [
            {
                "title": "CVE Program Container",
                "references": [
                    {
                        "url": "https://lists.debian.org/debian-lts-announce/2025/08/msg00010.html"
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