CVE-2021-38503 is a vulnerability that affects the Linux kernel's implementation of the Berkeley Packet Filter (BPF), which is used for network packet filtering and analysis. This vulnerability allows an attacker with local access to a system to escalate their privileges and gain root access to the affected device. The vulnerability was assigned a CVSS (Common Vulnerability Scoring System) score of 7.8 out of 10, indicating a high severity.
The vulnerability was first discovered by security researchers at Qualys in July 2021, who promptly reported it to the Linux kernel development team. The vulnerability was patched in the Linux kernel version 5.13.4, which was released on July 22, 2021. However, it was not until August 11, 2021, that the vulnerability was publicly disclosed, allowing attackers to potentially exploit it before systems could be updated.
Organizations are advised to update their Linux systems to the latest kernel version as soon as possible to mitigate the risk posed by CVE-2021-38503. Additionally, organizations should review their network security posture to ensure that appropriate measures are in place to detect and respond to any potential attacks exploiting this vulnerability.