Vulnerability identifier: #VU16578

Vulnerability risk: Low

CVSSv3.1: 6.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:C]

CVE-ID: CVE-2018-17204

CWE-ID: CWE-617

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Open vSwitch
Hardware solutions / Firmware

Vendor: openvswitch.org

Description

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

The vulnerability exists in parse_group_prop_ntr_selection_method in lib/ofp-util.c due to validation of the group type and command after the whole group mod has been decoded. A remote attacker can trigger an an assertion failure via OVS_NOT_REACHED when the OF1.5 decoder tries to use the type and command earlier, when it might still be invalid.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Open vSwitch: 2.7.0 - 2.7.6

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External links
http://github.com/openvswitch/ovs/commit/4af6da3b275b764b1afe194df6499b33d2bf4cde

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.