Information disclosure in Fortinet, FortiOS

1) Information disclosure

EUVDB-ID: #VU40173

Risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2015-5738

CWE-ID: CWE-200 - Information exposure

Exploit availability: No

Description

The vulnerability allows a remote non-authenticated attacker to gain access to sensitive information.

The RSA-CRT implementation in the Cavium Software Development Kit (SDK) 2.x, when used on OCTEON II CN6xxx Hardware on Linux to support TLS with Perfect Forward Secrecy (PFS), makes it easier for remote attackers to obtain private RSA keys by conducting a Lenstra side-channel attack.

Mitigation

Install update from vendor's website.

Vulnerable software versions

FortiOS: 5.0.12 - 5.4.0

External links

http://fortiguard.com/advisory/rsa-crt-key-leak-under-certain-conditions
http://people.redhat.com/~fweimer/rsa-crt-leaks.pdf
http://support.f5.com/kb/en-us/solutions/public/k/91/sol91245485.html

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.