Divide By Zero in Linux kernel - CVE-2012-2100

 

Divide By Zero in Linux kernel - CVE-2012-2100

Published: January 11, 2017 / Updated: March 16, 2017


Vulnerability identifier: #VU4198
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:A/U:Clear
CVE-ID: CVE-2012-2100
CWE-ID: CWE-369
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 attacker to cause DoS condition on the target system.

The weakness exists due to divide-by-zero error in the ext4_fill_flex_info() function. By using a malformed ext4 filesystem containing a super block with a large FLEX_BG group size (aka s_log_groups_per_flex value), a local attacker can trigger kernel panic.

Successful exploitation of the vulnerability results in denial of service on the vulnerable system.

Note: the vulnerability was being actively exploited.

How to mitigate CVE-2012-2100

Install update from vendor's website.

Sources