Rule Category

SERVER-OTHER -- Snort has detected traffic exploiting vulnerabilities in a server in the network.

Alert Message

SERVER-OTHER OpenSSL TLS record tampering denial of service attempt

Rule Explanation

The vulnerability occurs when OpenSSL client tries to establish a session but receives a Warning alert followed by a Handshake record with the a Finished message from the server, causing OpenSSL to terminate and thus create a Denial Of Service condition. The rule identifies the unique warning TLS record and finish handshake causing the DOS.

What To Look For

The vulnerability occurs when OpenSSL client tries to establish a session but receives a Warning alert followed by a Handshake record with the a Finished message from the server, causing OpenSSL to terminate and thus create a Denial Of Service condition.

Known Usage

No public information

False Positives

No known false positives

Contributors

Cisco Talos Intelligence Group

MITRE ATT&CK Framework

Tactic: Impact

Technique: Endpoint Denial of Service

For reference, see the MITRE ATT&CK vulnerability types here: https://attack.mitre.org

CVE

Additional Links

Rule Vulnerability

Denial of Service

Denial of Service attacks aim to make a server or program unresponsive for users. These attacks may be volume-based, to overwhelm the system, or they may use certain logical flaws in the software to cut the service off from the users. The attack may come from one or multiple sources. These attacks do not usually lead to a remote code execution. Volume based attacks are best handled using a firewall application.

CVE Additional Information

CVE-2013-4353
The ssl3_take_mac function in ssl/s3_both.c in OpenSSL 1.0.1 before 1.0.1f allows remote TLS servers to cause a denial of service (NULL pointer dereference and application crash) via a crafted Next Protocol Negotiation record in a TLS handshake.
Details
SeverityMEDIUM Base Score4.3
Impact Score2.9 Exploit Score8.6
Confidentiality ImpactNONE Integrity ImpactNONE
Availability ImpactPARTIAL Access Vector
AuthenticationNONE Ease of Access