{"api_version":"1","generated_at":"2026-09-26T15:01:40+00:00","cve":"CVE-2026-98012","urls":{"html":"https://cve.report/CVE-2026-98012","api":"https://cve.report/api/cve/CVE-2026-98012.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-98012","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-98012"},"summary":{"title":"net/sched: sfq: clamp quantum in change path","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: sfq: clamp quantum in change path\n\nsfq_change() accepts any non-negative quantum (only rejects\n(int)ctl->quantum < 0). With a crafted size table qdisc_pkt_len reaches\n~2 GiB, so quantum=1 makes the deficit-refill loop spin ~2^31 times\nunder the qdisc lock (a soft lockup / denial of service).\n\nAdd max(256U, ...) matching fq_codel_change(). Reject quantum > 1<<20\nwith -EINVAL, matching fq_codel_change() and the init clamp.\n\nConditions to recreate the bug:\n  CONFIG_NET_SCH_SFQ=y. Requires CAP_NET_ADMIN (namespace-local via\n  unshare -Urn suffices).\n\n  tc qdisc add dev dummy0 root sfq\n  tc qdisc change dev dummy0 root sfq quantum 1 stab data 32768 size_log 15 cell_log 0","state":"PUBLISHED","assigner":"Linux","published_at":"2026-09-25 11:17:29","updated_at":"2026-09-25 11:17:29"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/e6c1cb728e389354203a72bc77464c222a247aeb","name":"https://git.kernel.org/stable/c/e6c1cb728e389354203a72bc77464c222a247aeb","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/f3820dce042a673fcb28cc31c87ee14257e21a17","name":"https://git.kernel.org/stable/c/f3820dce042a673fcb28cc31c87ee14257e21a17","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/534cd7ecbbc6e8a974f4003a5c1557439c6e0a72","name":"https://git.kernel.org/stable/c/534cd7ecbbc6e8a974f4003a5c1557439c6e0a72","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/fb9f88a33c516ea5c0bcd9a22ca288b246b34567","name":"https://git.kernel.org/stable/c/fb9f88a33c516ea5c0bcd9a22ca288b246b34567","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98012","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98012","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 82bd38bd5467ece1ee274b493f51326cf5220a5a f3820dce042a673fcb28cc31c87ee14257e21a17 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e4650d7ae4252f67e997a632adfae0dd74d3a99a 534cd7ecbbc6e8a974f4003a5c1557439c6e0a72 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e4650d7ae4252f67e997a632adfae0dd74d3a99a e6c1cb728e389354203a72bc77464c222a247aeb git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e4650d7ae4252f67e997a632adfae0dd74d3a99a fb9f88a33c516ea5c0bcd9a22ca288b246b34567 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 843cacb88f42f426973f1ed11c6fb562558efb27 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 4919649699c5f4dbae08b8e2ed536fc9d6c3c2aa git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 548cf048b426729a7a1fa6acd1271c010c9a7380 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected c49ac48fac51a6a54efd5963954d02bacf075085 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 58ae7465f0e7113d45aa88a66bf2d203c71c195e git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.12.13 6.12.111 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.4.297 5.5 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.10.239 5.11 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.15.186 5.16 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.1.129 6.2 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.6.76 6.7 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.13","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.13 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.111 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.53 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.7 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3-rc3 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/sched/sch_sfq.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"f3820dce042a673fcb28cc31c87ee14257e21a17","status":"affected","version":"82bd38bd5467ece1ee274b493f51326cf5220a5a","versionType":"git"},{"lessThan":"534cd7ecbbc6e8a974f4003a5c1557439c6e0a72","status":"affected","version":"e4650d7ae4252f67e997a632adfae0dd74d3a99a","versionType":"git"},{"lessThan":"e6c1cb728e389354203a72bc77464c222a247aeb","status":"affected","version":"e4650d7ae4252f67e997a632adfae0dd74d3a99a","versionType":"git"},{"lessThan":"fb9f88a33c516ea5c0bcd9a22ca288b246b34567","status":"affected","version":"e4650d7ae4252f67e997a632adfae0dd74d3a99a","versionType":"git"},{"status":"affected","version":"843cacb88f42f426973f1ed11c6fb562558efb27","versionType":"git"},{"status":"affected","version":"4919649699c5f4dbae08b8e2ed536fc9d6c3c2aa","versionType":"git"},{"status":"affected","version":"548cf048b426729a7a1fa6acd1271c010c9a7380","versionType":"git"},{"status":"affected","version":"c49ac48fac51a6a54efd5963954d02bacf075085","versionType":"git"},{"status":"affected","version":"58ae7465f0e7113d45aa88a66bf2d203c71c195e","versionType":"git"},{"lessThan":"6.12.111","status":"affected","version":"6.12.13","versionType":"semver"},{"lessThan":"5.5","status":"affected","version":"5.4.297","versionType":"semver"},{"lessThan":"5.11","status":"affected","version":"5.10.239","versionType":"semver"},{"lessThan":"5.16","status":"affected","version":"5.15.186","versionType":"semver"},{"lessThan":"6.2","status":"affected","version":"6.1.129","versionType":"semver"},{"lessThan":"6.7","status":"affected","version":"6.6.76","versionType":"semver"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/sched/sch_sfq.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"6.13"},{"lessThan":"6.13","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.111","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.53","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.7","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3-rc3","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.111","versionStartIncluding":"6.12.13","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.53","versionStartIncluding":"6.13","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.7","versionStartIncluding":"6.13","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3-rc3","versionStartIncluding":"6.13","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.4.297","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10.239","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15.186","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1.129","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.6.76","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: sfq: clamp quantum in change path\n\nsfq_change() accepts any non-negative quantum (only rejects\n(int)ctl->quantum < 0). With a crafted size table qdisc_pkt_len reaches\n~2 GiB, so quantum=1 makes the deficit-refill loop spin ~2^31 times\nunder the qdisc lock (a soft lockup / denial of service).\n\nAdd max(256U, ...) matching fq_codel_change(). Reject quantum > 1<<20\nwith -EINVAL, matching fq_codel_change() and the init clamp.\n\nConditions to recreate the bug:\n  CONFIG_NET_SCH_SFQ=y. Requires CAP_NET_ADMIN (namespace-local via\n  unshare -Urn suffices).\n\n  tc qdisc add dev dummy0 root sfq\n  tc qdisc change dev dummy0 root sfq quantum 1 stab data 32768 size_log 15 cell_log 0"}],"providerMetadata":{"dateUpdated":"2026-09-25T10:23:35.934Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/f3820dce042a673fcb28cc31c87ee14257e21a17"},{"url":"https://git.kernel.org/stable/c/534cd7ecbbc6e8a974f4003a5c1557439c6e0a72"},{"url":"https://git.kernel.org/stable/c/e6c1cb728e389354203a72bc77464c222a247aeb"},{"url":"https://git.kernel.org/stable/c/fb9f88a33c516ea5c0bcd9a22ca288b246b34567"}],"title":"net/sched: sfq: clamp quantum in change path","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-98012","datePublished":"2026-09-25T10:23:35.934Z","dateReserved":"2026-09-25T10:19:56.069Z","dateUpdated":"2026-09-25T10:23:35.934Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-25 11:17:29","lastModifiedDate":"2026-09-25 11:17:29","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"98012","Ordinal":"1","Title":"net/sched: sfq: clamp quantum in change path","CVE":"CVE-2026-98012","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"98012","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: sfq: clamp quantum in change path\n\nsfq_change() accepts any non-negative quantum (only rejects\n(int)ctl->quantum < 0). With a crafted size table qdisc_pkt_len reaches\n~2 GiB, so quantum=1 makes the deficit-refill loop spin ~2^31 times\nunder the qdisc lock (a soft lockup / denial of service).\n\nAdd max(256U, ...) matching fq_codel_change(). Reject quantum > 1<<20\nwith -EINVAL, matching fq_codel_change() and the init clamp.\n\nConditions to recreate the bug:\n  CONFIG_NET_SCH_SFQ=y. Requires CAP_NET_ADMIN (namespace-local via\n  unshare -Urn suffices).\n\n  tc qdisc add dev dummy0 root sfq\n  tc qdisc change dev dummy0 root sfq quantum 1 stab data 32768 size_log 15 cell_log 0","Type":"Description","Title":"net/sched: sfq: clamp quantum in change path"}]}}}