Vulnerability identifier: #VU21598

Vulnerability risk: Low

CVSSv3.1: 3 [CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:N/I:N/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2019-17069

CWE-ID: CWE-399

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
PuTTY
Client/Desktop applications / Software for system administration

Vendor: Simon Tatham

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to an error when processing SSH1_MSG_DISCONNECT message. A remote attacker can trick the victim to connect to a remote SSH-1 server, send a specially crafted SSH1_MSG_DISCONNECT message and crash the affected PuTTY client.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

PuTTY: 0.45 - 0.72

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External links
http://lists.tartarus.org/pipermail/putty-announce/2019/000029.html

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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.