CVE-2019-9955 : What You Need to Know
Learn about CVE-2019-9955 affecting Zyxel ATP200, ATP500, ATP800, USG series, and ZyWALL series. Find out the impact, affected systems, exploitation mechanism, and mitigation steps.
Zyxel devices such as ATP200, ATP500, ATP800, USG series, and ZyWALL series are vulnerable to Reflected XSS on their login pages due to an unsanitized input parameter.
Understanding CVE-2019-9955
This CVE identifies a security vulnerability in Zyxel networking devices that can be exploited through a reflected cross-site scripting (XSS) attack.
What is CVE-2019-9955?
The login pages of various Zyxel devices are susceptible to a Reflected XSS vulnerability caused by the unsanitized 'mp_idx' input parameter.
The Impact of CVE-2019-9955
This vulnerability could allow attackers to execute malicious scripts in the context of a user's web browser, potentially leading to unauthorized actions or data theft.
Technical Details of CVE-2019-9955
Zyxel devices are affected by a specific vulnerability that can be exploited through the following technical details:
Vulnerability Description
The vulnerability lies in the login pages of Zyxel ATP200, ATP500, ATP800, USG series, and ZyWALL series devices, where the 'mp_idx' parameter is not properly sanitized, enabling attackers to inject and execute malicious scripts.
Affected Systems and Versions
- Products: ATP200, ATP500, ATP800, USG20-VPN, USG20W-VPN, USG40, USG40W, USG60, USG60W, USG110, USG210, USG310, USG1100, USG1900, USG2200-VPN, ZyWALL 110, ZyWALL 310, ZyWALL 1100
- Versions: All versions are affected
Exploitation Mechanism
The vulnerability can be exploited by crafting a malicious URL containing the unsanitized 'mp_idx' parameter, which when clicked by a user, executes the injected script in the user's browser.
Mitigation and Prevention
To address CVE-2019-9955 and enhance the security of Zyxel devices, consider the following mitigation strategies:
Immediate Steps to Take
- Disable remote access to the affected devices if not required
- Regularly monitor for any unusual activities on the network
- Implement network segmentation to limit the impact of potential attacks
Long-Term Security Practices
- Conduct regular security assessments and penetration testing
- Educate users about phishing attacks and safe browsing practices
- Keep devices up to date with the latest firmware and security patches
Patching and Updates
- Check for firmware updates from Zyxel's official website
- Apply patches promptly to address known vulnerabilities and enhance device security