In the Linux kernel, a high-severity vulnerability has been identified and subsequently resolved. This vulnerability allows attackers to exploit a use-after-free condition in the brcmf_netdev_start_xmit function within the wireless driver brcmfmac. The specific flaw occurs when a memory reference is freed while still being accessed, potentially leading to unauthorized access or system instability.
With a CVSS score of 7.8, the severity of this vulnerability is classified as high, indicating significant risk to organizations. The vulnerability can be exploited locally and requires low privileges, making it easier for attackers to execute malicious actions. Given the potential impacts on confidentiality, integrity, and availability, organizations should address this issue as a priority.
The vulnerability was published on September 18, 2025, and has since been modified in response to ongoing security assessments. Organizations running affected versions of the Linux kernel need to be aware of this vulnerability's existence and the associated risks, which include unauthorized data access and potential system crashes.
Organizations should prioritize patching immediately to mitigate the risks associated with this vulnerability. Regular updates and security practices can significantly reduce exposure to such vulnerabilities.
Vulnerability Details
The vulnerability in question is categorized under CWE-416, which pertains to use-after-free errors. This specific bug allows a task to read freed memory, leading to potential data corruption or unauthorized access. The vulnerability's description indicates that the bug manifests when the function brcmf_proto_tx_queue_data is called, and the memory reference is accessed after it has been freed.
The vulnerability is applicable to various versions of the Linux kernel, specifically those prior to version 4.14.296, between versions 4.15 and 4.19.262, and several others up to version 6.0.3. The high CVSS score indicates that this vulnerability poses significant risks, including high impacts on confidentiality, integrity, and availability.
Technical Analysis
The root cause of this vulnerability lies in improper memory management within the Linux kernel. Specifically, it involves a use-after-free condition where a pointer is accessed after the memory it points to has been deallocated. This can lead to unpredictable behavior, including system crashes and exploitation by an attacker.
The attack vector is local, meaning that an attacker must have access to the local system to exploit this vulnerability. The complexity of the attack is low, and it requires low privileges, making it easier for attackers to execute their actions. No user interaction is required, which further facilitates the exploitation of this vulnerability.
In terms of impacts, the vulnerability affects confidentiality, integrity, and availability. Successful exploitation could lead to unauthorized data access, modification of system states, and potential denial of service.
Risk & Impact Analysis
The real-world risk associated with this vulnerability is significant. Organizations using affected versions of the Linux kernel are at risk of potential unauthorized access to sensitive data and disruption of services. The blast radius is considerable, as this vulnerability can affect any system running the vulnerable kernel versions.
Given the high CVSS score, organizations should address this vulnerability in their patch cycles immediately. The lack of a public exploit and its absence from the KEV catalog suggest that active exploitation is currently not prevalent, but this could change.
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 by this vulnerability: all versions prior to 4.14.296, versions from 4.15 to 4.19.262, versions from 4.20 to 5.4.220, versions from 5.5 to 5.10.150, versions from 5.11 to 5.15.75, versions from 5.16 to 5.19.17, and versions from 6.0 to 6.0.3.
Mitigation & Remediation
Organizations should prioritize applying the patches provided by the Linux kernel maintainers to mitigate this vulnerability. The patches can be found in the official Linux kernel repositories. In cases where immediate patching is not feasible, organizations should consider implementing network controls and monitoring to detect any unusual behavior that may indicate exploitation attempts.
For more information on penetration testing to validate the effectiveness of your security measures, you can refer to our penetration testing services offered by AppSecure.
Detection Guidance
Organizations should monitor logs for indicators of exploitation related to this vulnerability, including any attempts to access freed memory or unusual network traffic patterns. Behavioral anomalies in applications may also indicate potential exploitation. Keeping an eye on system changes that deviate from the norm can be crucial in identifying exploitation attempts.
AppSecure Threat Intelligence Insight
The long-term significance of this vulnerability highlights the importance of vigilance in software development and maintenance. It serves as a reminder to security teams to regularly assess their systems for potential vulnerabilities and to maintain a proactive approach towards patch management.
This vulnerability represents a pattern of vulnerabilities related to memory management in kernel-level code. Organizations should learn from this incident to implement rigorous testing and code review processes to mitigate similar risks in the future.
For further reading on vulnerability management and best practices, consult our articles on vulnerability management programs, penetration testing methodology, and security testing best practices to enhance your organization's defenses against similar vulnerabilities.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
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