#VU31093 Race condition in Linux kernel - CVE-2019-3901
Published: April 22, 2019 / Updated: July 17, 2020
Vulnerability identifier: #VU31093
Vulnerability risk: Low
CVSSv4.0: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2019-3901
CWE-ID: CWE-362
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerable software:
Linux kernel
Linux kernel
Software vendor:
Linux Foundation
Linux Foundation
Description
The vulnerability allows a local authenticated user to gain access to sensitive information.
A race condition in perf_event_open() allows local attackers to leak sensitive data from setuid programs. As no relevant locks (in particular the cred_guard_mutex) are held during the ptrace_may_access() call, it is possible for the specified target task to perform an execve() syscall with setuid execution before perf_event_alloc() actually attaches to it, allowing an attacker to bypass the ptrace_may_access() check and the perf_event_exit_task(current) call that is performed in install_exec_creds() during privileged execve() calls. This issue affects kernel versions before 4.8.
Remediation
Install update from vendor's website.