#VU9595 Buffer overflow in OpenSSL - CVE-2017-3738

Vulnerability identifier: #VU9595

Vulnerability risk: Low

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2017-3738

CWE-ID: CWE-120

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
OpenSSL
Server applications / Encryption software

Vendor: OpenSSL Software Foundation

Description
The vulnerability allows a remote attacker to obtain potentially sensitive information on the target system.

The weakness exists due to buffer overflow in the AVX2 Montgomery multiplication procedure used in exponentiation with 1024-bit moduli. A remote attacker can cause the server to share the DH1024 private key among multiple clients and perform attack on TLS.

Mitigation
Update to version 1.0.2n.

Vulnerable software versions

OpenSSL: 1.0.1c - 1.0.1, 1.0.2l - 1.0.2

---

External links
https://www.openssl.org/news/secadv/20171207.txt

---

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.