SB2019081334 - Red Hat update for kernel
Published: August 13, 2019
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 4 secuirty vulnerabilities.
1) Improper input validation (CVE-ID: CVE-2017-17805)
The vulnerability allows a local attacker to cause DoS condition on the target system.The weakness exists due to the Salsa20 encryption algorithm in the Linux kernel does not correctly handle zero-length inputs. A local attacker able to use the AF_ALG-based skcipher interface (CONFIG_CRYPTO_USER_API_SKCIPHER) can trigger uninitialized-memory free and cause the kernel to crash or execute a specially crafted sequence of system calls that use the blkcipher_walk API.
Successful exploitation of the vulnerability results in denial of service.
2) Improper access control (CVE-ID: CVE-2018-17972)
The vulnerability allows a local user to gain access to potentially sensitive information.
The vulnerability exists within the proc_pid_stack() function in fs/proc/base.c due to the Linux kernel does not ensure that only root may inspect the kernel stack of an arbitrary task. A local user can exploit racy stack unwinding and leak kernel task stack contents.
3) Information disclosure (CVE-ID: CVE-2019-1125)
The vulnerability allows a local user to gain access to potentially sensitive information and elevate privileges on the system.
The vulnerability exists when certain central processing units (CPU) speculatively access memory. A local user can gain unauthorized access to sensitive information and elevate privileges on the system.
This issue is a variant of the Spectre Variant 1 speculative execution side channel vulnerability that leverages SWAPGS instructions to bypass KPTI/KVA mitigations.
4) Information disclosure (CVE-ID: CVE-2019-5489)
The vulnerability allows a local attacker to gain access to potentially sensitive information.
The vulnerability exists due to a flaw in the mincore() implementation in mm/mincore.c. A local attacker can observe page cache access patterns of other processes on the same system and sniff secret information.
Remediation
Install update from vendor's website.