CVE intelligence

CVE-2026-93167

Vulnerability intelligence

Published Sep 17, 2026Sources checked Nov 3, 2026

N/ACVSS not listedScore unavailable

What this means

Review the available evidence

CVE-2026-93167. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

CISA KEVNot listedBased on the latest collected catalog

EPSS0.2%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-93167?

In the Linux kernel, the following vulnerability has been resolved:

csky: Fix a4/a5 restoration in syscall trace path

The syscall trace path reloads syscall arguments from pt_regs before calling the syscall handler. On C-SKY ABIv2, the 5th and 6th syscall arguments are prepared as stack arguments before invoking syscallid.

The current code adjusts sp before loading LSAVE_A4 and LSAVE_A5. Since those offsets are relative to the original pt_regs base, loading them after changing sp fetches the wrong slots.

As a result, traced syscalls that use the 5th or 6th argument may receive corrupted arguments.

This is visible with mmap2(), which takes six arguments. A small PTRACE_SYSCALL reproducer opens a file and maps one page with:

mmap(NULL, 4096, PROT_READ | PROT_EXEC, MAP_PRIVATE, fd, 0)

Before the fix, the traced child fails the mmap and exits with 12. After the fix, the mapping succeeds and the child exits with 0.

Fix the trace path by loading a4/a5 from pt_regs before changing sp.

Tested on: ck860f, linux-4.19.15, C-SKY abiv2

Source: NVD