CVE-2022-49388 – This is a use-after-free vulnerability in the L... (How to Fix)

Q: What is the severity of CVE-2022-49388?

CVE-2022-49388 has a CVSS score of 7.8 (HIGH). This is a use-after-free vulnerability in the Linux kernel's UBI (Unsorted Block Images) subsystem that occurs when volume creation fails. It allows attackers with local access to potentially execute arbitrary code or cause denial of service by exploiting the freed memory. Systems running vulnerable Linux kernel versions with UBI enabled are affected.

📋 TL;DR

This is a use-after-free vulnerability in the Linux kernel's UBI (Unsorted Block Images) subsystem that occurs when volume creation fails. It allows attackers with local access to potentially execute arbitrary code or cause denial of service by exploiting the freed memory. Systems running vulnerable Linux kernel versions with UBI enabled are affected.

💻 Affected Systems

Products:

Linux kernel

Versions: Specific vulnerable versions not specified in CVE, but patches exist in stable kernel trees.

Operating Systems: Linux distributions using affected kernel versions

Default Config Vulnerable: ⚠️ Yes

Notes: Only affects systems with UBI (Unsorted Block Images) subsystem enabled, typically used with flash storage devices.

📦 What is this software?

Linux Kernel by Linux

The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...

Learn more about Linux Kernel →

Linux Kernel by Linux

The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...

Learn more about Linux Kernel →

Linux Kernel by Linux

The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...

Learn more about Linux Kernel →

Linux Kernel by Linux

The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...

Learn more about Linux Kernel →

Linux Kernel by Linux

The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...

Learn more about Linux Kernel →

Linux Kernel by Linux

The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...

Learn more about Linux Kernel →

Linux Kernel by Linux

The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...

Learn more about Linux Kernel →

⚠️ Risk & Real-World Impact

🔴

Worst Case

Local privilege escalation to kernel-level code execution, potentially leading to full system compromise.

🟠

Likely Case

Kernel panic or system crash causing denial of service.

🟢

If Mitigated

Limited impact if proper access controls prevent local user exploitation.

🌐 Internet-Facing: LOW - Requires local access to exploit.

🏢 Internal Only: MEDIUM - Malicious local users or compromised accounts could exploit this vulnerability.

🎯 Exploit Status

Public PoC: ✅ No

Weaponized: UNKNOWN

Unauthenticated Exploit: ✅ No

Complexity: MEDIUM

Requires local access and knowledge of UBI subsystem. No public exploit code available.

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: Patched in stable kernel versions via commits referenced in CVE

Vendor Advisory: https://git.kernel.org/stable/c/1174ab8ba36a48025b68b5ff1085000b1e510217

Restart Required: Yes

Instructions:

1. Update Linux kernel to patched version. 2. Check distribution-specific security advisories. 3. Reboot system after kernel update.

🔧 Temporary Workarounds

Disable UBI subsystem

Linux

Remove or disable UBI kernel module if not required

modprobe -r ubi
echo 'blacklist ubi' >> /etc/modprobe.d/blacklist.conf

🧯 If You Can't Patch

Restrict local user access to prevent exploitation
Implement strict access controls and monitoring for UBI-related operations

🔍 How to Verify

Check if Vulnerable:

Check kernel version and verify if UBI module is loaded: lsmod | grep ubi

Check Version:

uname -r

Verify Fix Applied:

Verify kernel version is updated and check for presence of fix commits in kernel source

📡 Detection & Monitoring

Log Indicators:

Kernel panic logs
UBI error messages in dmesg
System crash reports

Network Indicators:

None - local exploitation only

SIEM Query:

Search for kernel panic events or UBI subsystem errors in system logs

📊 Metadata

CVE ID: CVE-2022-49388

CVSS v3 Score: 7.8 (HIGH)

CVSS Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CWE: CWE-416

EPSS Score: 0.04% exploit probability (10.3th percentile)

Published: February 26, 2025

Last Updated: March 25, 2025

🔗 References

📤 Share & Export

📄 Export Markdown 📋 Export JSON

🔗 Related Vulnerabilities

If you're affected by CVE-2022-49388, you might also want to check these: