SB2017062218 - Ubuntu update for OpenVPN
Published: June 22, 2017
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 6 secuirty vulnerabilities.
1) Access control error (CVE-ID: CVE-2016-6329)
The vulnerability allows attackers to gain access to potentially sensitive information.
The vulnerability exists due to capturing of long duration Blowfish CBC mode encrypted TLS session. Repeated sending of communication protocol with parts of the plaintext helps attackers to reconstruct the secret information.
Successful exploitation of this vulnerability may allow a remote attacker to access potentially sensitive data.
2) Denial of service (CVE-ID: CVE-2017-7479)
The vulnerability allows a remote authenticated attacker to cause DoS conditions on the target system.The weakness exists due to improper user-input validation. A remote attacker can cause the packet-IDs on the target server to be consumed, trigger the server process to hit an ASSERT() and stop running.
Successful exploitation of the vulnerability of results in denial of service.
3) Improper input validation (CVE-ID: CVE-2017-7508)
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due assertion failure when processing IPv6 packets. A remote attacker can send a specially crafted IPv6 packet and perform a denial of service (DoS) attack.
4) Memory leak (CVE-ID: CVE-2017-7512)
The vulnerability allows a remote attacker to gain access to potentially sensitive information.
The vulnerability exists due to multiple errors. A remote attacker can trigger memory leak and gain unauthorized access to potentially sensitive information.
5) MitM attack (CVE-ID: CVE-2017-7520)
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack or obtain potentially sensitive client's information.
If clients use a HTTP proxy with NTLM authentication (i.e. "--http-proxy <server> <port> [<authfile>|'auto'|'auto-nct'] ntlm2"), a man-in-the-middle attacker between the client and the proxy can cause the client to crash or disclose at most 96 bytes of stack memory. The disclosed stack memory is likely to contain the proxy password.
6) Double free error (CVE-ID: CVE-2017-7521)
The vulnerability allows a remote attacker to compromise vulnerable system.
The vulnerability exists due to double free error when processing --x509-alt-username attribute. A remote unauthenticated attacker can trigger double free error and crash the affected server or potentially execute arbitrary code.
Successful exploitation of the vulnerability may allow an attacker to compromise vulnerable system.
Remediation
Install update from vendor's website.