high CVSS 7.8

CVE-2022-49186·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: clk: visconti: prevent array overflow in visconti_clk_register_gates() This code was using -1 to represent that there was no reset function. Unfortunately, the -1 was stored in u8 so the if (clks[i].rs_id >= 0) condition was always true. This lead to an out of bounds access in visconti_clk_register_gates().

Severity
high
Software
Kernel
Fixed in
5.17.2
Published
2025-02-26

Affected versions

From: 5.17

Until: 5.17.2

Fixed in: 5.17.2

How to fix this CVE

Update your Linux kernel to version 5.17.2 or later to patch a clock driver array overflow vulnerability affecting the Visconti platform. The flaw in the clk_visconti module could allow local attackers to trigger out-of-bounds memory access by exploiting improper validation of reset identifiers. Apply the patch immediately if you are running kernel 5.17.0, 5.17.1, or 5.17.2 on Visconti-based systems.

sudo dnf update kernel kernel-devel

Defensia detects this vulnerability

How to check if you are affected

  1. Step 1: Check your current kernel version with: uname -r
  2. Step 2: Verify if you are running a vulnerable version (5.17.0 to 5.17.1): grep -i '5\.17\.[0-1]' /proc/version
  3. Step 3: Check if the clk_visconti driver is loaded: lsmod | grep visconti_clk
  4. Step 4: After patching, reboot and verify the new version with: uname -r (should show 5.17.2 or higher)
  5. Step 5: Confirm the patched driver is in use: dmesg | grep -i visconti

FAQ

What is CVE-2022-49186?

CVE-2022-49186 is a local privilege escalation vulnerability in the Linux kernel's Visconti clock driver that results from incorrect type casting of a sentinel value. When a -1 indicator was stored in an unsigned 8-bit integer, the driver's bounds check always evaluated as true, causing out-of-bounds array access during gate clock registration.

Is CVE-2022-49186 being actively exploited?

No, this CVE is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog and no public exploits are currently available. However, the vulnerability requires local system access, limiting the attack surface.

What versions of Kernel are affected by CVE-2022-49186?

Linux kernel versions 5.17.0 through 5.17.1 are vulnerable. Version 5.17.2 and all subsequent releases contain the fix.

How do I check if my server is vulnerable to CVE-2022-49186?

Run: uname -r and check if the output matches 5.17.0 or 5.17.1. Also verify with: cat /proc/version | grep -E '5\.17\.[0-1]'

Does Defensia detect CVE-2022-49186?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Linux kernel is installed on a monitored server, CVE-2022-49186 will appear in your dashboard with remediation steps.

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References

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