avahi up to 0.6.32 avahi-daemon UDP Packet access control

Summaryinfo

A vulnerability, which was classified as critical, has been found in avahi up to 0.6.32. Affected is an unknown function of the component avahi-daemon. This manipulation as part of UDP Packet causes access control. The identification of this vulnerability is CVE-2017-6519. It is possible to initiate the attack remotely. There is no exploit available. It is advisable to implement restrictive firewalling.

Detailsinfo

A vulnerability has been found in avahi up to 0.6.32 and classified as critical. Affected by this vulnerability is an unknown functionality of the component avahi-daemon. The manipulation as part of a UDP Packet leads to a access control vulnerability. The CWE definition for the vulnerability is CWE-284. The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. As an impact it is known to affect confidentiality, and availability. The summary by CVE is:

avahi-daemon in Avahi through 0.6.32 and 0.7 inadvertently responds to IPv6 unicast queries with source addresses that are not on-link, which allows remote attackers to cause a denial of service (traffic amplification) and may cause information leakage by obtaining potentially sensitive information from the responding device via port-5353 UDP packets. NOTE: this may overlap CVE-2015-2809.

The bug was discovered 05/05/2017. The weakness was shared 05/01/2017 (Website). It is possible to read the advisory at bugzilla.redhat.com. This vulnerability is known as CVE-2017-6519 since 03/07/2017. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1068 according to MITRE ATT&CK.

The commercial vulnerability scanner Qualys is able to test this issue with plugin 197360 (Ubuntu Security Notification for Avahi Vulnerabilities (USN-3876-1)).

Proper firewalling of udp/5353 is able to address this issue.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2017-15575). The entry VDB-128175 is related to this item. Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Name

• avahi

Version

• 0.6.0
• 0.6.1
• 0.6.2
• 0.6.3
• 0.6.4
• 0.6.5
• 0.6.6
• 0.6.7
• 0.6.8
• 0.6.9
• 0.6.10
• 0.6.11
• 0.6.12
• 0.6.13
• 0.6.14
• 0.6.15
• 0.6.16
• 0.6.17
• 0.6.18
• 0.6.19
• 0.6.20
• 0.6.21
• 0.6.22
• 0.6.23
• 0.6.24
• 0.6.25
• 0.6.26
• 0.6.27
• 0.6.28
• 0.6.29
• 0.6.30
• 0.6.31
• 0.6.32

CPE 2.3info

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CPE 2.2info

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Be aware that VulDB is the high quality source for vulnerability data.

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