Rule Category

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

Alert Message

SERVER-OTHER Open SSL 1.0.2 DoS attempt with an invalid signature algorithm

Rule Explanation

The sigalgs implementation in t1_lib.c in OpenSSL 1.0.2 before 1.0.2a allows remote attackers to cause a denial of service (NULL pointer dereference and daemon crash) by using an invalid signature_algorithms extension in the ClientHello message during a renegotiation. Impact: CVSS base score 5.0 CVSS impact score 2.9 CVSS exploitability score 10.0 confidentialityImpact NONE integrityImpact NONE availabilityImpact NONE Details: Ease of Attack:

What To Look For

Known Usage

No public information

False Positives

No known false positives

Contributors

Talos research team. This document was generated from data supplied by the national vulnerability database, a product of the national institute of standards and technology. For more information see [nvd].

MITRE ATT&CK Framework

Tactic:

Technique:

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

CVE

Additional Links

Rule Vulnerability

CVE Additional Information

CVE-2015-0291
The sigalgs implementation in t1_lib.c in OpenSSL 1.0.2 before 1.0.2a allows remote attackers to cause a denial of service (NULL pointer dereference and daemon crash) by using an invalid signature_algorithms extension in the ClientHello message during a renegotiation.
Details
SeverityMEDIUM Base Score5.0
Impact Score2.9 Exploit Score10.0
Confidentiality ImpactNONE Integrity ImpactNONE
Availability ImpactPARTIAL Access Vector
AuthenticationNONE Ease of Access