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Vulnerabilities
Vulnerability

CVE-2026-31423

Reference data from vuln.mlab.sh, coverage from our own index.

CVSS
5.5 Medium
Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS
0.12%
Risk score
1.1
Published
2026-04-13
Status
Published

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. A flaw was found in the Linux kernel's Hierarchical Fair Service Curve (HFSC) network scheduler. When processing specific large input values, a calculation error can cause a variable to be truncated to zero. This zero value is then used as a divisor, leading to a divide-by-zero error and a system crash, resulting in a Denial of Service (DoS).

Weaknesses

CWE-369

Coverage 6

Advisories and references