CVE-2021-25811 Explained : Impact and Mitigation
Discover the impact of CVE-2021-25811, a DoS vulnerability in MERCUSYS Mercury X18G 1.0.5 devices. Learn about affected versions, exploitation mechanisms, and mitigation strategies.
A Denial of Service vulnerability has been identified in MERCUSYS Mercury X18G 1.0.5 devices. Attackers can exploit this vulnerability through a crafted value in the POST listen_http_lan parameter, leading to a DoS condition. Subsequent device restarts exacerbate the issue, rendering the device unable to access the webserver unless the listen_http_lan parameter in uhttpd.json is manually corrected.
Understanding CVE-2021-25811
This section delves into the details of the CVE-2021-25811 vulnerability, its impacts, technical aspects, and mitigation strategies.
What is CVE-2021-25811?
CVE-2021-25811 refers to a Denial of Service vulnerability in the MERCUSYS Mercury X18G 1.0.5 devices caused by malicious input leading to a persistent webserver access issue.
The Impact of CVE-2021-25811
Exploitation of this vulnerability can result in a complete denial of service, rendering the device inaccessible to the webserver even after reboots until manual intervention is carried out.
Technical Details of CVE-2021-25811
Let's explore the technical specifics of the CVE-2021-25811 vulnerability in detail.
Vulnerability Description
The vulnerability arises from a flaw in the POST listen_http_lan parameter processing, allowing attackers to disrupt device operation.
Affected Systems and Versions
MERCUSYS Mercury X18G devices running version 1.0.5 are impacted by this vulnerability, exposing them to potential DoS attacks.
Exploitation Mechanism
By sending a crafted value to the POST listen_http_lan parameter, threat actors can trigger the DoS condition, leading to severe service disruption.
Mitigation and Prevention
To safeguard against CVE-2021-25811, it is crucial to implement immediate and long-term protective measures.
Immediate Steps to Take
Network administrators should explore immediate mitigations to neutralize the vulnerability's exploitation and restore device accessibility.
Long-Term Security Practices
Establishing robust security practices, regular system audits, and employee training sessions can fortify defenses against similar vulnerabilities.
Patching and Updates
Vendor-released patches should be promptly applied to affected devices to eliminate the vulnerability and secure network infrastructure.