{"id":"AZL-82694","summary":"CVE-2026-31423 affecting package kernel for versions less than 6.6.134.1-2","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: sch_hfsc: fix divide-by-zero in rtsc_min()\n\nm2sm() converts a u32 slope to a u64 scaled value.  For large inputs\n(e.g. m1=4000000000), the result can reach 2^32.  rtsc_min() stores\nthe difference of two such u64 values in a u32 variable `dsm` and\nuses it as a divisor.  When the difference is exactly 2^32 the\ntruncation yields zero, causing a divide-by-zero oops in the\nconcave-curve intersection path:\n\n  Oops: divide error: 0000\n  RIP: 0010:rtsc_min (net/sched/sch_hfsc.c:601)\n  Call Trace:\n   init_ed (net/sched/sch_hfsc.c:629)\n   hfsc_enqueue (net/sched/sch_hfsc.c:1569)\n   [...]\n\nWiden `dsm` to u64 and replace do_div() with div64_u64() so the full\ndifference is preserved.","modified":"2026-08-28T17:47:55.857056587Z","published":"2026-04-13T14:16:12Z","upstream":["CVE-2026-31423"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-31423"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.6.134.1-2"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-82694.json"}}],"schema_version":"1.9.0"}