CVE-2019-11823 : Security Advisory and Response

An issue with CRLF injection vulnerability has been found in Synology Router Manager (SRM) version 1.2.3-8017-2 and earlier versions. This vulnerability, present in the Network Center, can be exploited by remote attackers to execute a denial of service attack by sending manipulated network traffic.

Understanding CVE-2019-11823

This CVE involves a CRLF injection vulnerability in Synology Router Manager (SRM) that allows remote attackers to cause a denial of service through crafted network traffic.

What is CVE-2019-11823?

CVE-2019-11823 is a CRLF injection vulnerability in the Network Center component of Synology Router Manager (SRM) versions prior to 1.2.3-8017-2. This vulnerability can be abused by attackers to trigger a denial of service attack.

The Impact of CVE-2019-11823

The vulnerability has a CVSS base score of 8.6, indicating a high severity level. The impact includes:

Attackers can exploit the vulnerability remotely without requiring privileges.
It can lead to a denial of service by causing an out-of-bounds read and application crash.
Confidentiality and integrity impacts are none, but availability impact is high.

Technical Details of CVE-2019-11823

CVE-2019-11823 involves a specific vulnerability in Synology Router Manager (SRM) that can be further understood through the following technical details:

Vulnerability Description

The vulnerability is categorized as CWE-125: Out-of-bounds Read, allowing attackers to crash the application through crafted network traffic.

Affected Systems and Versions

Product: Synology Router Manager (SRM)
Vendor: Synology
Versions Affected: < 1.2.3-8017-2 (unspecified/custom version)

Exploitation Mechanism

Attackers can exploit the vulnerability by sending manipulated network traffic to the Network Center, causing an out-of-bounds read and crashing the application.

Mitigation and Prevention

To address CVE-2019-11823, consider the following mitigation strategies:

Immediate Steps to Take

Update Synology Router Manager (SRM) to version 1.2.3-8017-2 or later to eliminate the vulnerability.
Monitor network traffic for any suspicious activity that could indicate an exploitation attempt.

Long-Term Security Practices

Regularly update and patch all software and firmware to prevent known vulnerabilities.
Implement network segmentation and access controls to limit the impact of potential attacks.

Patching and Updates

Stay informed about security advisories from Synology and apply patches promptly to secure your systems.