CVEvulnerability
CVE-2026-74685
- Status
- Received
- Published
- 2026-08-22
- Last modified
- 2026-10-14
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Description
In the Linux kernel, the following vulnerability has been resolved:
hwmon: (ltc4282) Clamp negative current limits
When a negative value is passed to ltc4282_write_curr(), the signed long
val is cast directly to u64:
drivers/hwmon/ltc4282.c:ltc4282_write_curr() {
/* need to pass it in millivolt */
u32 in = DIV_ROUND_CLOSEST_ULL((u64)val * st->rsense, DECA * MICRO);
...
}
This cast converts negative inputs into large positive values. The
subsequent division result overflows the u32 in variable, truncating
to a pseudo-random positive value. When this is passed to
ltc4282_write_voltage_byte(), it is clamped to the maximum limit instead
of zero.
Clamp val to 0 and to the maximum supported upper limit before the cast
and assign the result to a 64-bit temporary variable before the division
to avoid the underflow and an also possible overflow.
References
- https://git.kernel.org/stable/c/046e56b53c09375ef39903514496aa5508db9729 git.kernel.org
- https://git.kernel.org/stable/c/60e06c4dba696173982393252a40ceb7dd2eec18 git.kernel.org
- https://git.kernel.org/stable/c/de58b90a4d1417c15b693eb04c0ce6bc925d84c6 git.kernel.org
- https://git.kernel.org/stable/c/e253dd5f9f6d875a317895bf43ec9534ed7523cb git.kernel.org