In the Linux kernel, a significant vulnerability identified as CVE-2021-47670 has been addressed. The vulnerability stems from a use-after-free bug in the peak_usb driver, which could potentially allow attackers to exploit the system. This vulnerability is classified with a CVSS score of 7.8, indicating a high severity level. Organizations utilizing affected versions of the Linux kernel should be particularly vigilant, as the exploitability of this vulnerability presents real-world risks.
The risk to organizations includes unauthorized access and control of the affected systems, which could lead to significant data breaches or system integrity issues. With the attack vector being local and the privileges required being low, the threshold for potential exploitation is notably reduced, making it critical for organizations to address this vulnerability urgently.
Currently, there are no known exploits available for this vulnerability, but the potential for exploitation remains a concern. Organizations should prioritize patching immediately to safeguard their systems from potential threats that may arise.
Given the high severity of this vulnerability, it is essential for organizations to integrate this patch into their security protocols without delay. The Linux kernel patches addressing this issue have been released, and remediation should be part of the priority patch cycle.
Vulnerability Details
The CVE-2021-47670 vulnerability is characterized by a use-after-free issue within the Linux kernel's peak_usb driver. After executing the peak_usb_netif_rx_ni(skb) function, the subsequent dereferencing of the skb variable is unsafe. Specifically, the can_frame cf, which shares memory with skb, is accessed after the peak_usb_netif_rx_ni() call, leading to potential memory corruption.
This vulnerability has a CVSS 3.1 score of 7.8, indicating high severity. It has a local attack vector, low attack complexity, and requires low privileges, making it accessible to potential attackers. The impacts on confidentiality, integrity, and availability are all rated as high, reflecting the critical nature of this vulnerability.
CWE-416 is the relevant weakness classification associated with this vulnerability, further emphasizing the importance of addressing memory management issues in software development.
Technical Analysis
The root cause of the CVE-2021-47670 vulnerability lies in the improper handling of memory within the peak_usb driver of the Linux kernel. When the peak_usb_netif_rx_ni(skb) function is called, the subsequent access to the skb variable can lead to dereferencing freed memory, resulting in unsafe behavior that can be exploited.
The attack vector is classified as local, meaning that exploitation requires access to the local system. The complexity of the attack is low, and it necessitates low privileges, allowing even unprivileged users to potentially trigger the vulnerability. User interaction is not required for exploitation, further increasing the risk.
The impacts of this vulnerability are severe, with high ratings for confidentiality, integrity, and availability. This indicates that successful exploitation could lead to significant compromise of system data and functionality.
Risk & Impact Analysis
The deployment of the affected Linux kernel versions across various environments amplifies the risk associated with CVE-2021-47670. Organizations utilizing these kernel versions are at risk of potential exploitation, which could lead to unauthorized access and significant operational disruptions.
The blast radius of this vulnerability is considerable, as it affects local users who may be able to execute code with high privileges. The urgency of addressing this vulnerability is underscored by its CVSS score of 7.8, indicating it should be prioritized for remediation efforts.
Organizations should assess their exposure and prioritize patching efforts accordingly. The absence of known exploits does not diminish the threat potential, as attackers continuously seek to exploit unpatched vulnerabilities.
Exploitation Status
Signal | Status |
|---|---|
Known Exploit | No |
Public PoC | No |
Actively Exploited | No |
Ransomware Use | No |
Affected Versions
The following Linux kernel versions are affected by CVE-2021-47670: versions from 4.0 up to, but not including, 4.19.171; from 4.20 up to, but not including, 5.4.93; from 5.5 up to, but not including, 5.10.11; and specific release candidates of version 5.11 (rc1, rc2, rc3, and rc4). Organizations should ensure they are running the latest patched versions to mitigate the vulnerability.
Mitigation & Remediation
To remediate CVE-2021-47670, organizations should apply the available patches from the Linux kernel maintainers immediately. If patches are not immediately applicable, consider implementing temporary workarounds that mitigate the use-after-free condition. Configuration hardening, including restricting user privileges and monitoring system logs for unusual activities, can also help mitigate risks.
For ongoing protection and assessment, organizations should engage in continuous penetration testing to identify similar vulnerabilities in their systems.
Detection Guidance
Organizations should monitor system logs for any indicators of exploitation attempts related to CVE-2021-47670. Look for abnormal memory access patterns, particularly in relation to the peak_usb driver. Behavioral anomalies within the kernel that deviate from normal operations may also indicate potential exploitation.
AppSecure Threat Intelligence Insight
The CVE-2021-47670 vulnerability underscores the importance of rigorous memory management practices within system-level software. As vulnerabilities of this nature continue to emerge, organizations should adopt comprehensive security programs that include regular vulnerability assessments and code audits.
Security teams should also stay informed about trends in vulnerability exposure and take proactive measures to address potential weaknesses in their systems. For further insights, refer to the following resources: vulnerability management program and penetration testing methodology guides.
By maintaining a proactive stance towards security and integrating lessons learned from past vulnerabilities, organizations can significantly enhance their defenses against future threats.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
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