In the Linux kernel, the following vulnerability has been resolved: vsock/bpf: return early if transport is not assigned. Some of the core functions can only be called if the transport has been assigned. As Michal reported, a socket might have the transport at NULL, for example after a failed connect(), causing a kernel NULL pointer dereference. This issue can lead to a crash in the kernel, which poses a significant risk.
The severity of this vulnerability is classified as medium, with a CVSS score of 5.5. This level of severity indicates moderate risk and should not be overlooked by organizations utilizing affected versions of the Linux kernel.
Organizations are at risk due to the potential for high availability impact, leading to service disruptions. Attackers may leverage this vulnerability to cause system instability. Urgency for defenders is high, and patching efforts should be prioritized to mitigate these risks.
Currently, there are no known public exploits for this vulnerability, but organizations should remain vigilant and ensure their systems are updated with the latest patches.
Vulnerability Details
The vulnerability description states that a socket may have the transport set to NULL after a failed connection attempt. This flaw can lead to a kernel panic if core functions are called without ensuring that the transport is assigned. The CVSS vector for this vulnerability is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H, which indicates that the attack vector is local, attack complexity is low, and availability impact is high.
Affected products include the Linux kernel versions starting from 6.4 up to but not including 6.6.74, as well as various release candidates of version 6.13.
Technical Analysis
The root cause of the vulnerability lies in the failure to check whether the transport is assigned before invoking certain functions. This oversight can occur during socket operations. The attack vector is local, requiring the attacker to have access to the system. The complexity of the attack is low, as the attacker can simply exploit the condition leading to the NULL dereference.
No user interaction is required to exploit this vulnerability, making it easier for attackers to leverage it. The confidentiality and integrity impact are both negligible, but the availability impact is high, as it may lead to system crashes.
Risk & Impact Analysis
Real-world deployment risk is significant given that many Linux systems may be running vulnerable versions of the kernel. The potential for service disruption due to system crashes is a critical concern. Organizations must assess their current kernel versions and prioritize remediation efforts. The availability impact of this vulnerability could lead to downtime, affecting business operations and customer trust.
The urgency for patching is classified as high. Organizations should address this vulnerability in their priority patch cycle, ensuring that systems are updated to prevent potential exploitation.
Exploitation Status
Signal | Status |
|---|---|
Known Exploit | No |
Public PoC | No |
Actively Exploited | No |
Ransomware Use | No |
Affected Versions
The following versions of the Linux kernel are affected: All versions from 6.4 to less than 6.6.74, as well as specific release candidates from 6.13: rc1, rc2, rc3, rc4, rc5, rc6, and rc7.
Mitigation & Remediation
Organizations should prioritize patching immediately. The recommended action is to upgrade to the latest stable version of the Linux kernel. If patching is not feasible, consider implementing configuration hardening to minimize exposure to this vulnerability. Continuous monitoring and network controls should also be employed to detect any unusual activities related to this issue.
Detection Guidance
Monitoring should focus on log indicators that highlight any kernel panic events, as well as behavioral anomalies associated with socket operations. Network signatures that identify unusual traffic related to socket connections should also be established.
AppSecure Threat Intelligence Insight
The long-term significance of this vulnerability highlights the need for robust testing and validation of kernel updates. Security teams should ensure that they are aware of any vulnerabilities introduced in new kernel releases and take proactive measures to safeguard their systems. This incident serves as a reminder of the importance of continuous security assessments, such as penetration testing and regular updates to security policies.
Additionally, organizations should implement a thorough application security assessment process to identify and mitigate risks associated with their applications.
Finally, integrating insights from this vulnerability into broader security frameworks can enhance preparedness for future threats. Consider leveraging services like red teaming to simulate potential attack scenarios.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
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