CVE-2023-3567

Q: What is the severity of CVE-2023-3567?

CVE-2023-3567 has a CVSS score of 7.1 (HIGH). This CVE describes a use-after-free vulnerability in the Linux kernel's virtual console screen driver (vc_screen). An attacker with local user access can exploit this flaw to cause a system crash (denial of service) or potentially leak internal kernel memory information. This affects Linux systems with the vulnerable kernel versions.

7.1 HIGH

Denial of Service

📋 TL;DR

This CVE describes a use-after-free vulnerability in the Linux kernel's virtual console screen driver (vc_screen). An attacker with local user access can exploit this flaw to cause a system crash (denial of service) or potentially leak internal kernel memory information. This affects Linux systems with the vulnerable kernel versions.

💻 Affected Systems

Products:

Linux Kernel

Versions: Specific affected versions not provided in CVE description; check Red Hat advisories for exact ranges.

Operating Systems: Linux distributions using affected kernel versions

Default Config Vulnerable: ⚠️ Yes

Notes: Requires local user access; virtual console functionality must be enabled.

📦 What is this software?

Enterprise Linux by Redhat

View all CVEs affecting Enterprise Linux →

Enterprise Linux by Redhat

View all CVEs affecting Enterprise Linux →

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

Kernel panic leading to system crash and denial of service, or information disclosure of sensitive kernel memory contents.

🟠

Likely Case

Local denial of service through system crash or kernel panic.

🟢

If Mitigated

Minimal impact if proper access controls prevent local user exploitation.

🌐 Internet-Facing: LOW - Requires local user access, not remotely exploitable.

🏢 Internal Only: MEDIUM - Local users can cause system crashes or information leaks.

🎯 Exploit Status

Public PoC: ✅ No

Weaponized: UNKNOWN

Unauthenticated Exploit: ✅ No

Complexity: MEDIUM

Exploitation requires local user access and knowledge of kernel memory layout.

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: Check specific kernel version in Red Hat advisories (e.g., kernel-5.14.0-427.13.1.el9_4)

Vendor Advisory: https://access.redhat.com/errata/RHSA-2024:0412

Restart Required: Yes

Instructions:

1. Update kernel package using distribution's package manager. 2. Reboot system to load new kernel.

🔧 Temporary Workarounds

Restrict local user access

linux

Limit local user accounts to trusted users only.

🧯 If You Can't Patch

Implement strict access controls to limit local user accounts.
Monitor system logs for kernel panic or crash events.

🔍 How to Verify

Check if Vulnerable:

Check kernel version against patched versions in Red Hat advisories.

Check Version:

uname -r

Verify Fix Applied:

Verify kernel version after update matches patched version from advisory.

📡 Detection & Monitoring

Log Indicators:

Kernel panic messages in /var/log/messages or dmesg
System crash/reboot events

SIEM Query:

Search for 'kernel panic' or 'Oops' in system logs.

📊 Metadata

CVE ID: CVE-2023-3567

CVSS v3 Score: 7.1 (HIGH)

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

CWE: CWE-416

Published: July 24, 2023

Last Updated: November 21, 2024

📋 TL;DR

💻 Affected Systems

📦 What is this software?

Enterprise Linux by Redhat

Enterprise Linux by Redhat

Linux Kernel by Linux

Linux Kernel by Linux

Linux Kernel by Linux

Linux Kernel by Linux

Linux Kernel by Linux

Linux Kernel by Linux

Linux Kernel by Linux

Ubuntu Linux by Canonical

Ubuntu Linux by Canonical

Ubuntu Linux by Canonical

Ubuntu Linux by Canonical

Ubuntu Linux by Canonical

⚠️ Risk & Real-World Impact

Worst Case

Likely Case

If Mitigated

🎯 Exploit Status

🛠️ Fix & Mitigation

✅ Official Fix

Instructions:

🔧 Temporary Workarounds

Restrict local user access

🧯 If You Can't Patch

🔍 How to Verify

Check if Vulnerable:

Check Version:

Verify Fix Applied:

📡 Detection & Monitoring

Log Indicators:

SIEM Query:

📊 Metadata

🔗 References

📤 Share & Export

🔗 Related Vulnerabilities