{"api_version":"1","generated_at":"2026-06-26T20:55:29+00:00","cve":"CVE-2026-52997","urls":{"html":"https://cve.report/CVE-2026-52997","api":"https://cve.report/api/cve/CVE-2026-52997.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-52997","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-52997"},"summary":{"title":"net/sched: sch_dualpi2: drain both C-queue and L-queue in dualpi2_change()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: sch_dualpi2: drain both C-queue and L-queue in dualpi2_change()\n\nFix dualpi2_change() to correctly enforce updated limit and memlimit\nvalues after a configuration change of the dualpi2 qdisc.\n\nBefore this patch, dualpi2_change() always attempted to dequeue packets\nvia the root qdisc (C-queue) when reducing backlog or memory usage, and\nunconditionally assumed that a valid skb will be returned. When traffic\nclassification results in packets being queued in the L-queue while the\nC-queue is empty, this leads to a NULL skb dereference during limit or\nmemlimit enforcement.\n\nThis is fixed by first dequeuing from the C-queue path if it is\nnon-empty. Once the C-queue is empty, packets are dequeued directly from\nthe L-queue. Return values from qdisc_dequeue_internal() are checked for\nboth queues. When dequeuing from the L-queue, the parent qdisc qlen and\nbacklog counters are updated explicitly to keep overall qdisc statistics\nconsistent.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-06-24 17:17:10","updated_at":"2026-06-24 17:17:10"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/86cf2eba2056bcf9c41fba260e599bd95bf9943b","name":"https://git.kernel.org/stable/c/86cf2eba2056bcf9c41fba260e599bd95bf9943b","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/3042add80c2c50bd127d570b83319af612efde65","name":"https://git.kernel.org/stable/c/3042add80c2c50bd127d570b83319af612efde65","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/478ed6b7d2577439c610f91fa8759a4c878a4264","name":"https://git.kernel.org/stable/c/478ed6b7d2577439c610f91fa8759a4c878a4264","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-52997","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-52997","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 320d031ad6e4d67e8e1ab08ac71efda02bc85683 86cf2eba2056bcf9c41fba260e599bd95bf9943b git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 320d031ad6e4d67e8e1ab08ac71efda02bc85683 3042add80c2c50bd127d570b83319af612efde65 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 320d031ad6e4d67e8e1ab08ac71efda02bc85683 478ed6b7d2577439c610f91fa8759a4c878a4264 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.17","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.17 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.33 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.0.10 7.0.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"52997","cve":"CVE-2026-52997","epss":"0.001730000","percentile":"0.069770000","score_date":"2026-06-25","updated_at":"2026-06-26 00:06:15"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/sched/sch_dualpi2.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"86cf2eba2056bcf9c41fba260e599bd95bf9943b","status":"affected","version":"320d031ad6e4d67e8e1ab08ac71efda02bc85683","versionType":"git"},{"lessThan":"3042add80c2c50bd127d570b83319af612efde65","status":"affected","version":"320d031ad6e4d67e8e1ab08ac71efda02bc85683","versionType":"git"},{"lessThan":"478ed6b7d2577439c610f91fa8759a4c878a4264","status":"affected","version":"320d031ad6e4d67e8e1ab08ac71efda02bc85683","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/sched/sch_dualpi2.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"6.17"},{"lessThan":"6.17","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.33","versionType":"semver"},{"lessThanOrEqual":"7.0.*","status":"unaffected","version":"7.0.10","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.33","versionStartIncluding":"6.17","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.0.10","versionStartIncluding":"6.17","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1","versionStartIncluding":"6.17","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: sch_dualpi2: drain both C-queue and L-queue in dualpi2_change()\n\nFix dualpi2_change() to correctly enforce updated limit and memlimit\nvalues after a configuration change of the dualpi2 qdisc.\n\nBefore this patch, dualpi2_change() always attempted to dequeue packets\nvia the root qdisc (C-queue) when reducing backlog or memory usage, and\nunconditionally assumed that a valid skb will be returned. When traffic\nclassification results in packets being queued in the L-queue while the\nC-queue is empty, this leads to a NULL skb dereference during limit or\nmemlimit enforcement.\n\nThis is fixed by first dequeuing from the C-queue path if it is\nnon-empty. Once the C-queue is empty, packets are dequeued directly from\nthe L-queue. Return values from qdisc_dequeue_internal() are checked for\nboth queues. When dequeuing from the L-queue, the parent qdisc qlen and\nbacklog counters are updated explicitly to keep overall qdisc statistics\nconsistent."}],"providerMetadata":{"dateUpdated":"2026-06-24T16:29:09.997Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/86cf2eba2056bcf9c41fba260e599bd95bf9943b"},{"url":"https://git.kernel.org/stable/c/3042add80c2c50bd127d570b83319af612efde65"},{"url":"https://git.kernel.org/stable/c/478ed6b7d2577439c610f91fa8759a4c878a4264"}],"title":"net/sched: sch_dualpi2: drain both C-queue and L-queue in dualpi2_change()","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-52997","datePublished":"2026-06-24T16:29:09.997Z","dateReserved":"2026-06-09T07:44:35.377Z","dateUpdated":"2026-06-24T16:29:09.997Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-06-24 17:17:10","lastModifiedDate":"2026-06-24 17:17:10","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"52997","Ordinal":"1","Title":"net/sched: sch_dualpi2: drain both C-queue and L-queue in dualpi","CVE":"CVE-2026-52997","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"52997","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: sch_dualpi2: drain both C-queue and L-queue in dualpi2_change()\n\nFix dualpi2_change() to correctly enforce updated limit and memlimit\nvalues after a configuration change of the dualpi2 qdisc.\n\nBefore this patch, dualpi2_change() always attempted to dequeue packets\nvia the root qdisc (C-queue) when reducing backlog or memory usage, and\nunconditionally assumed that a valid skb will be returned. When traffic\nclassification results in packets being queued in the L-queue while the\nC-queue is empty, this leads to a NULL skb dereference during limit or\nmemlimit enforcement.\n\nThis is fixed by first dequeuing from the C-queue path if it is\nnon-empty. Once the C-queue is empty, packets are dequeued directly from\nthe L-queue. Return values from qdisc_dequeue_internal() are checked for\nboth queues. When dequeuing from the L-queue, the parent qdisc qlen and\nbacklog counters are updated explicitly to keep overall qdisc statistics\nconsistent.","Type":"Description","Title":"net/sched: sch_dualpi2: drain both C-queue and L-queue in dualpi"}]}}}