SB2018092520 - Fedora EPEL 6 update for gnutls30

Description

This security bulletin contains information about 4 secuirty vulnerabilities.

1) Null pointer dereference (CVE-ID: CVE-2017-7507)

The vulnerability allows a remote attacker to cause DoS condition on the target system.

The weakness exists due to NULL pointer dereference while decoding a status response TLS extension with valid contents. A remote attacker can send specially crafted status_request extension in a ClientHello message to cause the GnuTLS server application to crash.

Successful exploitation of the vulnerability results in denial of service.

2) Use of a broken or risky cryptographic algorithm (CVE-ID: CVE-2018-10844)

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to usage of an insecure implementation of HMAC-SHA-256 algorithm vulnerable to a Lucky thirteen style attack. A remote attacker with ability to intercept traffic can recover encrypted data.

3) Use of a broken or risky cryptographic algorithm (CVE-ID: CVE-2018-10845)

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to usage of an insecure implementation of HMAC-SHA-384 algorithm vulnerable to a Lucky thirteen style attack. A remote attacker with ability to intercept traffic can recover encrypted data.

4) Cryptographic issues (CVE-ID: CVE-2018-10846)

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to a cache-based side channel in GnuTLS implementation that can lead to recovery of data in cross-VM attack setting. A remote attacker with ability to intercept traffic can recover encrypted data using a combination of "Just in Time" Prime+probe attack in combination with Lucky-13 attack.

Remediation

Install update from vendor's website.

References

• https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2018-b4c337857d