A use-after-free flaw was found in the Linux kernel’s Netfilter functionality when adding a rule with NFTA_RULE_CHAIN_ID. This flaw allows a local user to crash or escalate their privileges on the system. The vulnerability has a CVSS score of 7.8, categorizing it as high severity. The potential for exploitation is significant, and organizations should prioritize patching immediately to safeguard their systems against this vulnerability.
Risk to organizations includes unauthorized access, potential data breaches, and system downtime. Given the nature of this vulnerability, it is critical for affected organizations to assess their environments and implement necessary patches without delay.
Currently, there is a known exploit available, making this vulnerability even more urgent for remediation. Organizations should take immediate action to mitigate the associated risks.
The vulnerability was published on August 7, 2023, and has been marked as modified in the CVE database. Continuous monitoring for updates and advisories is advised to ensure systems remain secure.
Vulnerability Details
This vulnerability allows a local user to crash or escalate their privileges on the system. The vulnerability type is classified as use-after-free, which is associated with CWE-416. The Linux kernel's Netfilter functionality is the affected component, with a CVSS score of 7.8 indicating high severity.
The attack vector is local, and the attack complexity is low, requiring only low privileges to exploit. User interaction is not required for this vulnerability to be exploited, which can lead to significant impacts on confidentiality, integrity, and availability.
Technical Analysis
The root cause of this vulnerability is a flaw in the memory management of the Netfilter functionality within the Linux kernel. When a rule is added with NFTA_RULE_CHAIN_ID, the system fails to properly handle memory allocation and deallocation, leading to a use-after-free condition.
The attack vector is local, allowing an attacker with access to the system to exploit this vulnerability easily. The complexity of executing this attack is low, as it requires only low privileges and no user interaction. The potential impacts include high confidentiality, integrity, and availability impacts, making it a critical vulnerability.
Risk & Impact Analysis
Real-world deployment risk includes the possibility of unauthorized access to sensitive data or system resources, leading to data breaches or system crashes. Organizations using affected versions of the Linux kernel should assess their environment and apply patches as soon as they become available.
The urgency of addressing this vulnerability is high due to its CVSS score, known exploitation status, and the significant impact it can have on organizations. The blast radius is substantial, as multiple distributions of Linux are affected, including Debian and Red Hat.
Signal | Status |
|---|---|
Known Exploit | Yes |
Public PoC | Yes |
Actively Exploited | No |
Ransomware Use | No |
Affected Versions
The vulnerability affects various versions of the Linux kernel, including but not limited to the following:
All versions prior to vendor patch, specifically versions 5.9 to 5.15.124, 5.16 to 6.1.43, and 6.2 to 6.4.8, are vulnerable.
Mitigation & Remediation
Organizations should prioritize patching immediately. Upgrading to the latest version of the Linux kernel that addresses this vulnerability is essential. If a patch is unavailable, workarounds such as restricting user access to affected systems and implementing additional monitoring may be necessary.
Configuration hardening, including limiting local user privileges and ensuring proper firewall rules, can further mitigate risks. Regular monitoring for unusual system behavior and log analysis is recommended to detect any exploitation attempts.
For more information on how to protect your systems, organizations can refer to our penetration testing services.
Detection Guidance
Log indicators related to this vulnerability include unexpected crashes in the Netfilter functionality and unauthorized changes to firewall rules. Organizations should monitor for behavioral anomalies that deviate from normal operational patterns.
Network signatures indicating exploitation attempts should be established to detect unusual traffic patterns that may indicate an attack leveraging this vulnerability.
AppSecure Threat Intelligence Insight
The long-term significance of this vulnerability highlights the ongoing challenges in software security, particularly in widely used components such as the Linux kernel. This incident underscores the need for robust vulnerability management practices.
Security teams should learn from this vulnerability to enhance their defensive strategies, focusing on timely patching and monitoring of critical systems.
For further reading on vulnerability management and security best practices, refer to our vulnerability management program design guide.
Additionally, our penetration testing methodology article provides valuable insights into proactive security measures.
Finally, organizations should consider engaging in red teaming services to identify potential weaknesses before they can be exploited.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
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