CVE-2023-54030

Vulnerability

Overview In the Linux kernel's io_uring subsystem, a flaw exists in the handling of multishot recv operations. The issue allows for an overflow of Completion Queue Events (CQEs) when using multishot receive requests. This can lead to excessive resource consumption, potentially causing out-of-memory (OOM) conditions for the task or significantly degrading performance [1].

Exploitation

Details To exploit this vulnerability, an attacker requires the ability to submit io_uring requests with the multishot recv flag. This typically involves having access to the io_uring interface, which may be available to unprivileged users on many Linux systems. By sending a large number of multishot recv operations, the attacker can cause CQE overflow, overwhelming the system's ability to process events efficiently [1].

Impact

The primary impact of this vulnerability is resource exhaustion. An attacker could cause the target system to run out of memory or suffer severe performance degradation. This could result in denial of service (DoS) conditions, preventing legitimate processes from executing correctly. There is no indication in the provided references of code execution or privilege escalation [1].

Mitigation

The Linux kernel has addressed this vulnerability by implementing a fix that prevents the overflow of multishot recv CQEs. The patch is included in the stable kernel tree and can be applied via standard kernel updates [1]. Systems should update to a kernel version containing this fix to mitigate the risk.