SB2018090401 - OpenSUSE Linux update for libressl
Published: September 4, 2018
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 2 secuirty vulnerabilities.
1) Memory-cache side-channel timing attack (CVE-ID: CVE-2018-12434)
The vulnerability allows a local attacker to obtain potentially sensitive information.
The vulnerability exists due to information leak via memory caches when modular addition calculations may not run in constant time when private keys are used to generate Elliptic Curve Digital Signature Algorithm (ECDSA) or Digital Signature Algorithm (DSA) signatures. A local attacker can conduct memory-cache side-channel timing attacks and recover sensitive information, such as the ECDSA or DSA private keys used to generate the signatures, which could be used to conduct additional attacks.
2) Cryptographic issues (CVE-ID: CVE-2018-8970)
The vulnerability allows a remote attacker to perform a spoofing attack.
The vulnerability exists due to the int_x509_param_set_hosts() function in lib/libcrypto/x509/x509_vpm.c does not correctly handle a case where hostname lenght is zero that leads to silent hostname omission during domain name verification process.
A remote unauthenticated attacker can create a specially crafted certificate, perform a man-in-the-middle (MitM) attack and gain access to sensitive information.
Remediation
Install update from vendor's website.