CVE-2019-1763 : Security Advisory and Response

Cisco IP Phone 8800 Series Authorization Bypass Vulnerability

Understanding CVE-2019-1763

A security weakness in the web-based management interface of SIP Software for Cisco IP Phone 8800 Series allows unauthorized remote attackers to bypass authorization, access critical services, and potentially cause a denial of service (DoS) situation.

What is CVE-2019-1763?

The vulnerability arises due to improper URL filtering in the software, enabling attackers to submit specially crafted URLs to gain unauthorized access to critical services.

The Impact of CVE-2019-1763

Attack Complexity: Low
Attack Vector: Network
Availability Impact: High
Base Score: 7.5 (High Severity)
Scope: Unchanged
User Interaction: None
Vector String: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE-284

Technical Details of CVE-2019-1763

A vulnerability in the web-based management interface of SIP Software for Cisco IP Phone 8800 Series.

Vulnerability Description

Allows unauthenticated remote attackers to bypass authorization
Enables access to critical services
Potential for a denial of service (DoS) scenario

Affected Systems and Versions

Cisco Wireless IP Phone 8821 and 8821-EX running SIP Software version prior to 11.0(5)
Cisco IP Conference Phone 8832 and the rest of the IP Phone 8800 Series running SIP Software version prior to 12.5(1)SR1

Exploitation Mechanism

Attackers exploit the vulnerability by submitting crafted URLs
Successful exploitation grants unauthorized access to critical services

Mitigation and Prevention

Immediate Steps to Take:

Apply vendor-provided patches promptly
Monitor Cisco's security advisories for updates

Long-Term Security Practices:

Regularly update software and firmware
Implement network segmentation and access controls

Patching and Updates:

Update Cisco IP Phone 8800 Series to versions 11.0(5) or higher for Wireless IP Phone 8821 and 8821-EX, and 12.5(1)SR1 or higher for the IP Conference Phone 8832 and the rest of the IP Phone 8800 Series