#VU9333 Denial of service in OpenSSH - CVE-2017-15906

Vulnerability identifier: #VU9333

Vulnerability risk: Low

CVSSv4.0: 4.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2017-15906

CWE-ID: CWE-264

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
OpenSSH
Server applications / Remote management servers, RDP, SSH

Vendor: OpenSSH

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

The weakness exists in the process_open() function due to improper prevention of write operations in read-only mode. A remote attacker can create zero-length files and cause the service to crash.

Successful exploitation of the vulnerability results in denial of service.

Mitigation
Update to version 7.6.

Vulnerable software versions

OpenSSH: 3.6.1p2 - 7.5p1

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External links
https://www.openssh.com/txt/release-7.6

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.