Integer overflow in Linux kernel - CVE-2018-12896

 

Integer overflow in Linux kernel - CVE-2018-12896

Published: July 2, 2018 / Updated: April 3, 2019


Vulnerability identifier: #VU92788
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2018-12896
CWE-ID: CWE-190
Exploitation vector: Local access
Exploit availability: No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel

Detailed vulnerability description

The vulnerability allows a local user to perform a denial of service (DoS) attack.

An issue was discovered in the Linux kernel through 4.17.3. An Integer Overflow in kernel/time/posix-timers.c in the POSIX timer code is caused by the way the overrun accounting works. Depending on interval and expiry time values, the overrun can be larger than INT_MAX, but the accounting is int based. This basically makes the accounting values, which are visible to user space via timer_getoverrun(2) and siginfo::si_overrun, random. For example, a local user can cause a denial of service (signed integer overflow) via crafted mmap, futex, timer_create, and timer_settime system calls.


How to mitigate CVE-2018-12896

Install update from vendor's repository.

Sources