SB2019050903 - OpenSUSE Linux update for gnutls
Published: May 9, 2019
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 3 secuirty vulnerabilities.
1) Cache Attacks (CVE-ID: CVE-2018-16868)
The vulnerability allows a remote attacker to perform a downgrade attack on the server and decrypt private keys on the target system.The vulnerability exists due to a core weakness in TLS that relates to the handshaking of the session key which is used within the tunnel during parallelisation of thousands of oracle queries that occurs using a cluster of TLS servers which share the same public key certificate. A remote attacker can mount a microarchitectural side channel attack against a vulnerable implementation, obtain a network man-in-the-middle position, obtain the relevant data to sign and trigger the victim server to decrypt ciphertexts chosen by the adversary to perform a downgrade attack.
2) Double free (CVE-ID: CVE-2019-3829)
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to a double free error in the certificate verification API when processing X.509 crtificates. A remote attacker can supply a specially crafted X.509 certificate, trigger double free error and execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
3) Buffer overflow (CVE-ID: CVE-2019-3836)
The vulnerability allows a remote attacker to perform denial of service attack.
The vulnerability exists due to uninitialized pointer access when processing TLS1.3 asynchronous messages. A remote attacker can pass specially crafted asynchronous post-handshake message, trigger memory corruption and perform denial of service attack.
Remediation
Install update from vendor's website.