SB2016101004 - Multiple vulnerabilities in OpenSSL
Published: October 10, 2016 Updated: February 23, 2017
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 3 secuirty vulnerabilities.
1) Information disclosure (CVE-ID: CVE-2016-7055)
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.
2) NULL pointer dereference (CVE-ID: CVE-2016-7053)
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.
3) Heap overflow (CVE-ID: CVE-2016-7054)
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.
Remediation
Install update from vendor's website.