SB2018071123 - Red Hat update for kernel
Published: July 11, 2018 Updated: July 16, 2018
Security Bulletin ID
SB2018071123
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
2
Exploitation vector
Local access
Highest impact
Denial of service
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 2 vulnerabilities.
1) Divide by zero (CVE-ID: CVE-2017-14106)
CWE-ID: CWE-369 - Divide By Zero
CVSSv4: 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
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 tcp_disconnect() function in net/ipv4/tcp.c. A local attacker can trigger a disconnect within a certain tcp_recvmsg code path and cause kernel panic.
Successful exploitation of the vulnerability results in denial of service.
2) Speculative Store Bypass (CVE-ID: CVE-2018-3639)
CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local attacker to obtain potentially sensitive information on the target system.
The weakness exists due to race conditions in CPU cache processing. A local attacker can conduct a side-channel attack to exploit a flaw in the speculative execution of Load and Store instructions to read privileged memory.
Note: the vulnerability is referred to as "Spectre variant 4".
Remediation
Install update from vendor's website.