Rule Category

POLICY-OTHER --

Alert Message

POLICY-OTHER SSLv3 Client Hello attempt

Rule Explanation

The design of the Internet Key Exchange (IKE) protocol, when using Aggressive Mode for shared secret authentication, does not encrypt initiator or responder identities during negotiation, which may allow remote attackers to determine valid usernames by (1) monitoring responses before the password is supplied or (2) sniffing, as originally reported for FireWall-1 SecuRemote. Impact: CVSS base score 5.0 CVSS impact score 2.9 CVSS exploitability score 10.0 confidentialityImpact PARTIAL integrityImpact NONE availabilityImpact NONE Details: Ease of Attack:

What To Look For

This rule alerts when an attempt to identify if SSL version 3 is being used by a system.

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: Discovery

Technique: System Network Configuration Discovery

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

CVE

Rule Vulnerability

CVE Additional Information

CVE-2002-1623
The design of the Internet Key Exchange (IKE) protocol, when using Aggressive Mode for shared secret authentication, does not encrypt initiator or responder identities during negotiation, which may allow remote attackers to determine valid usernames by (1) monitoring responses before the password is supplied or (2) sniffing, as originally reported for FireWall-1 SecuRemote.
Details
SeverityMEDIUM Base Score5.0
Impact Score2.9 Exploit Score10.0
Confidentiality ImpactPARTIAL Integrity ImpactNONE
Availability ImpactNONE Access Vector
AuthenticationNONE Ease of Access
CVE-2013-2566
The RC4 algorithm, as used in the TLS protocol and SSL protocol, has many single-byte biases, which makes it easier for remote attackers to conduct plaintext-recovery attacks via statistical analysis of ciphertext in a large number of sessions that use the same plaintext.
Details
Severity Base Score5.9
Impact Score3.6 Exploit Score2.2
Confidentiality ImpactHIGH Integrity ImpactNONE
Availability ImpactNONE Access Vector
Authentication Ease of Access