Multiple vulnerabilities in OpenSSL

1) Information disclosure

EUVDB-ID: #VU5894

Risk: Low

CVSSv3.1: 3.5 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:N/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2016-7055

CWE-ID: CWE-310 - Cryptographic Issues

Exploit availability: No

Description

The vulnerability allows a remote attacker to decrypt certain data.

The vulnerability exists in OpenSSL implementation due to propagating bug in the Broadwell-specific Montgomery multiplication procedure that handles input lengths divisible by, but longer than 256 bits. A remote attacker can launch attacks against RSA, DSA and DH private keys and decrypt information, passed over encrypted channels. Among EC algorithms only Brainpool P-512 curves are affected and one presumably can attack ECDH key negotiation.

Successful exploitation of the vulnerability may allow an attacker in certain conditions to launch attacks against OpenSSL clients.

Mitigation

Update OpenSSL to version  1.0.2 or 1.1.0c.

Vulnerable software versions

OpenSSL: 1.0.1 - 1.1.0b

External links

http://www.openssl.org/news/secadv/20161110.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.

2) NULL pointer dereference

EUVDB-ID: #VU5893

Risk: Medium

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

CVE-ID: CVE-2016-7053

CWE-ID: CWE-476 - NULL Pointer Dereference

Exploit availability: No

Description

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

The vulnerability exists due to NULL pointer dereference error when parsing ASN.1 CHOICE type within CMS structures in OpenSSL. A remote attacker can send a specially crafted request to vulnerable service and initiate the NULL value being passed to the structure callback if an attempt is made to free certain invalid encodings.

Successful exploitation may result in denial of service (DoS) attack.

Mitigation

OpenSSL 1.1.0 users should upgrade to 1.1.0c

This issue does not affect OpenSSL versions prior to 1.1.0

Vulnerable software versions

OpenSSL: 1.1.0 - 1.1.0b

External links

http://www.openssl.org/news/secadv/20161110.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.

3) Heap overflow

EUVDB-ID: #VU5892

Risk: Medium

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-2016-7054

CWE-ID: CWE-122 - Heap-based Buffer Overflow

Exploit availability: Yes

Description

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

The vulnerability exists due to a boundary error when processing *-CHACHA20-POLY1305 TLS ciphersuites (ChaCha20/Poly1305) in OpenSSL. A remote attacker can send large payloads to affected service, triggering heap overflow. 

Successful exploitation of the vulnerability may result in denial of service (DoS) conditions.

Mitigation

OpenSSL 1.1.0 users should upgrade to 1.1.0c

This issue does not affect OpenSSL versions prior to 1.1.0

Vulnerable software versions

OpenSSL: 1.1.0 - 1.1.0b

External links

http://www.openssl.org/news/secadv/20161110.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. However, proof of concept for this vulnerability is available.