CVE-2026-31423net/sched: sch_hfsc: fix divide-by-zero in rtsc_min()
Updated under an hour ago ()
Does this affect you?
It affects Linux and 4 other products. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
Do this next
Free account, 1 product
In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_hfsc: fix divide-by-zero in rtsc_min() m2sm() converts a u32 slope to a u64 scaled value. For large inputs (e.g. m1=4000000000), the result can reach 2^32. rtsc_min() stores the difference of two such u64 values in a u32 variable `dsm` and uses it as a divisor. When the difference is exactly 2^32 the truncation yields zero, causing a divide-by-zero oops in the concave-curve intersection path: Oops: divide error: 0000 RIP: 0010:rtsc_min (net/sched/sch_hfsc.c:601) Call Trace: init_ed (net/sched/sch_hfsc.c:629) hfsc_enqueue (net/sched/sch_hfsc.c:1569) [...] Widen `dsm` to u64 and replace do_div() with div64_u64() so the full difference is preserved.
- CVSS
- 5.5 MEDIUM (v3.1, NVD)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Weakness (CWE)
- Not given
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- Linux
- NVD analysis
- Modified
- Record last updated
- Oct 15, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
Linux Linux linux:linux (from the name) | from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 before ad8e8fec40290a8c8cf145c0deaadf76f80c5163; from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 before ab1ff5890c7354afc7be56502fcfbd61f3b7ae4f; from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 before 25b6821884713a31e2b49fb67b0ebd765b33e0a9; from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 before c56f78614e7781aaceca9bd3cb2128bf7d45c3bd; from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 before b9e6431cbea8bb1fae8069ed099b4ee100499835; from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 before 17c1b9807b8a67d676b6dcf749ee932ebaa7f568; from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 before d0aefec1b1a1ba2c1d251028dc2c4e5b4ce1fea5; from 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 before 4576100b8cd03118267513cafacde164b498b322 | CNA record |
Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP siemens:simatic_s7_1500_cpu_1518_4_pn_dp_mfp (from the name) | from V3.1.6 | CISA ADP |
Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP siemens:simatic_s7_1500_cpu_1518f_4_pn_dp_mfp (from the name) | from V3.1.6 | CISA ADP |
Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP siemens:siplus_s7_1500_cpu_1518_4_pn_dp_mfp (from the name) | from V3.1.6 | CISA ADP |
linux linux_kernel linux:linux_kernel | from 2.6.12.1 before 5.10.253; from 5.11 before 5.15.203; from 5.16 before 6.1.168; from 6.2 before 6.6.134; from 6.7 before 6.12.81; from 6.13 before 6.18.22; from 6.19 before 6.19.12; 2.6.12; and 10 more ranges | NVD |
References
- https://git.kernel.org/stable/c/ad8e8fec40290a8c8cf145c0deaadf76f80c5163patch
- https://git.kernel.org/stable/c/ab1ff5890c7354afc7be56502fcfbd61f3b7ae4fpatch
- https://git.kernel.org/stable/c/25b6821884713a31e2b49fb67b0ebd765b33e0a9patch
- https://git.kernel.org/stable/c/c56f78614e7781aaceca9bd3cb2128bf7d45c3bdpatch
- https://git.kernel.org/stable/c/b9e6431cbea8bb1fae8069ed099b4ee100499835patch
- https://git.kernel.org/stable/c/17c1b9807b8a67d676b6dcf749ee932ebaa7f568patch
- https://git.kernel.org/stable/c/d0aefec1b1a1ba2c1d251028dc2c4e5b4ce1fea5patch
- https://git.kernel.org/stable/c/4576100b8cd03118267513cafacde164b498b322patch
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html
- https://cert-portal.siemens.com/productcert/html/ssa-082556.html
- https://cert-portal.siemens.com/productcert/html/ssa-457936.html
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.