CVE-2018-0051 Explained : Impact and Mitigation
Learn about CVE-2018-0051, a Denial of Service vulnerability in Junos OS SIP ALG component, impacting Juniper Networks SRX Series. Find out the affected versions and mitigation steps.
A vulnerability in the SIP application layer gateway (ALG) component of Junos OS based platforms has been identified, allowing an attacker to crash various processes.
Understanding CVE-2018-0051
This CVE involves a Denial of Service vulnerability in MS-PIC, MS-MIC, MS-MPC, MS-DPC, and SRX flow daemon (flowd) related to SIP ALG.
What is CVE-2018-0051?
The vulnerability in the SIP ALG component of Junos OS platforms enables attackers to crash critical processes like MS-PIC, MS-MIC, MS-MPC, MS-DPC, or SRX flow daemon (flowd).
The Impact of CVE-2018-0051
- CVSS Base Score: 7.5 (High Severity)
- Attack Vector: Network
- Availability Impact: High
- Attack Complexity: Low
- No malicious exploitation reported by Juniper SIRT
Technical Details of CVE-2018-0051
Vulnerability Description
The vulnerability allows attackers to crash essential processes on Junos OS devices with NAT or stateful firewall configurations and enabled SIP ALG.
Affected Systems and Versions
- Platforms: SRX Series
- Versions affected: 12.1X46-D77, 12.3X48-D70, 15.1X49-D140, 15.1F6, 15.1R4-S9, 15.1R7-S1, 16.1R4-S9, 16.1R6-S1, 16.1R7, 16.2R2-S7, 16.2R3, 17.1R2-S7, 17.1R3, 17.2R1-S6, 17.2R2-S4, 17.2R3, 17.3R1-S5, 17.3R2-S2, 17.3R3, 17.4R2
Exploitation Mechanism
The vulnerability can be exploited by attackers to crash critical processes on Junos OS devices with specific configurations and SIP ALG enabled.
Mitigation and Prevention
Immediate Steps to Take
- Disable SIP ALG feature if not required
Long-Term Security Practices
- Regularly update Junos OS to the patched versions
- Implement network segmentation and access controls
- Conduct regular security audits
Patching and Updates
- Update to the following software releases: 12.1X46-D77, 12.3X48-D70, 15.1X49-D140, 15.1F6, 15.1R4-S9, 15.1R7-S1, 16.1R4-S9, 16.1R6-S1, 16.1R7, 16.2R2-S7, 16.2R3, 17.1R2-S7, 17.1R3, 17.2R1-S6, 17.2R2-S4, 17.2R3, 17.3R1-S5, 17.3R2-S2, 17.3R3, 17.4R2, 18.1R1, 18.1X75-D10, 18.2R1, 18.2X75-D5, and subsequent releases.
- Proactive fixes have been applied to other releases without SIP ALG support.