SB2015050809 - Ubuntu update for linux
Published: May 8, 2015 Updated: October 31, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 4 vulnerabilities.
1) Buffer overflow (CVE-ID: CVE-2011-4086)
CWE-ID: CWE-119 - Memory corruption
CVSSv4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote non-authenticated attacker to perform a denial of service (DoS) attack.
The journal_unmap_buffer function in fs/jbd2/transaction.c in the Linux kernel before 3.3.1 does not properly handle the _Delay and _Unwritten buffer head states, which allows local users to cause a denial of service (system crash) by leveraging the presence of an ext4 filesystem that was mounted with a journal.
2) Input validation error (CVE-ID: CVE-2012-1090)
CWE-ID: CWE-20 - Improper input validation
CVSSv4: 6.8 [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]
The vulnerability allows a local authenticated user to perform a denial of service (DoS) attack.
The cifs_lookup function in fs/cifs/dir.c in the Linux kernel before 3.2.10 allows local users to cause a denial of service (OOPS) via attempted access to a special file, as demonstrated by a FIFO.
3) Divide By Zero (CVE-ID: CVE-2012-2100)
CWE-ID: CWE-369 - Divide By Zero
CVSSv4: 6.8 [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]
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.
4) Input validation error (CVE-ID: CVE-2012-4398)
CWE-ID: CWE-20 - Improper input validation
CVSSv4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote non-authenticated attacker to perform a denial of service (DoS) attack.
The __request_module function in kernel/kmod.c in the Linux kernel before 3.4 does not set a certain killable attribute, which allows local users to cause a denial of service (memory consumption) via a crafted application.
Remediation
Install update from vendor's website.