CVE-2019-12677 : Vulnerability Insights and Analysis
Learn about CVE-2019-12677, a vulnerability in Cisco ASA Software SSL VPN feature allowing remote attackers to cause denial of service. Find mitigation steps here.
A vulnerability in the SSL VPN feature of Cisco Adaptive Security Appliance (ASA) Software allows a remote attacker to cause a denial of service (DoS) condition by mishandling Base64-encoded strings.
Understanding CVE-2019-12677
This CVE involves a flaw in the SSL VPN feature of Cisco ASA Software, impacting the establishment of new SSL/TLS connections to the device.
What is CVE-2019-12677?
The vulnerability in SSL VPN feature of Cisco ASA Software enables an authenticated remote attacker to trigger a DoS condition, hindering new SSL/TLS connections to the affected device.
The Impact of CVE-2019-12677
- Attack Complexity: Low
- Attack Vector: Network
- Availability Impact: High
- Base Score: 7.7 (High)
- Scope: Changed
- Privileges Required: Low
- User Interaction: None
- Confidentiality Impact: None
- Integrity Impact: None
Technical Details of CVE-2019-12677
This section provides detailed technical information about the vulnerability.
Vulnerability Description
The flaw arises from the mishandling of Base64-encoded strings in the SSL VPN feature, allowing an attacker to initiate numerous SSL VPN sessions, leading to memory allocation errors.
Affected Systems and Versions
- Product: Cisco Adaptive Security Appliance (ASA) Software
- Vendor: Cisco
- Version: Unspecified
Exploitation Mechanism
- Attacker needs valid user credentials
- Initiates multiple SSL VPN sessions
- Overwrites system memory location
- Results in memory allocation errors for new SSL/TLS sessions
Mitigation and Prevention
Protect your systems from this vulnerability with the following steps:
Immediate Steps to Take
- Monitor for any unusual SSL VPN session activity
- Implement network traffic monitoring and anomaly detection
- Apply vendor-recommended patches and updates
Long-Term Security Practices
- Regularly review and update access controls
- Conduct security awareness training for users
- Perform regular security assessments and audits
Patching and Updates
- Apply the latest security patches provided by Cisco
- Keep the SSL VPN feature up to date with recommended updates