CVE-2026-2329 is a critical vulnerability identified in the Grandstream GXP1600 series of VoIP phones. This vulnerability allows an unauthenticated stack-based buffer overflow via the HTTP API endpoint /cgi-bin/api.values.get. A remote attacker can leverage this vulnerability to achieve unauthenticated remote code execution (RCE) with root privileges on a target device, which poses a significant risk to organizations using these devices.
With a CVSS score of 9.3, this vulnerability is classified as critical. Organizations should prioritize patching immediately to mitigate the risk of potential exploitation. The urgency is underscored by the fact that this vulnerability affects multiple models within the GXP1600 series, including the GXP1610, GXP1615, GXP1620, GXP1625, GXP1628, and GXP1630.
Given the nature of this vulnerability, attackers may leverage it to gain full control over affected devices, leading to unauthorized access to sensitive communications and data. The exploitation status is currently unknown, as there is no evidence of public exploits or proof-of-concept code available at this time.
Organizations using Grandstream GXP1600 series devices are urged to review their systems and apply necessary patches as soon as they become available. The risk to organizations includes potential unauthorized access and control over VoIP communications, which could lead to data breaches and operational disruptions.
Vulnerability Details
The vulnerability described in CVE-2026-2329 is characterized by a stack-based buffer overflow that occurs within the HTTP API endpoint. This vulnerability affects the following Grandstream GXP1600 series firmware versions: GXP1610, GXP1615, GXP1620, GXP1625, GXP1628, and GXP1630.
The vulnerability classification falls under CWE-121, indicating an improper restriction of operations within the bounds of a memory buffer. The risk posed by this vulnerability reinforces the importance of secure coding practices and regular software updates.
Published on February 18, 2026, the critical nature of this vulnerability warrants immediate attention from security teams managing affected devices.
Technical Analysis
The root cause of CVE-2026-2329 lies in the implementation of the HTTP API endpoint /cgi-bin/api.values.get that fails to properly validate input, leading to a stack-based buffer overflow. This vulnerability allows attackers to exploit the system remotely over the network without any form of authentication.
The attack vector is classified as NETWORK, indicating that exploitation can occur remotely without physical access to the device. The attack complexity is categorized as LOW, which suggests that exploiting this vulnerability does not require advanced skills or resources.
No privileges are required for exploitation, and user interaction is not necessary, making this vulnerability particularly dangerous. The potential impact includes high confidentiality, integrity, and availability risks.
Risk & Impact Analysis
The real-world deployment risk associated with CVE-2026-2329 is significant. Organizations using any of the affected Grandstream devices should recognize the potential for unauthorized access and control over their VoIP communications. The blast radius for this vulnerability is extensive, given that it impacts multiple device models.
Risk to organizations includes potential data breaches, unauthorized surveillance, and severe operational disruptions. Given the critical CVSS score and the nature of the vulnerability, organizations should address this in their priority patch cycle.
The urgency for remediation is underscored by the fact that attackers may exploit this vulnerability to gain root access, leading to further attacks within the network. Organizations should remain vigilant and prepare for potential exploitation attempts.
Exploitation Status
Signal | Status |
|---|---|
Known Exploit | No |
Public PoC | No |
Actively Exploited | No |
Ransomware Use | No |
Affected Versions
The affected versions include the following firmware for the Grandstream GXP1600 series: GXP1610, GXP1615, GXP1620, GXP1625, GXP1628, and GXP1630. All versions prior to the vendor patch are at risk.
Mitigation & Remediation
Organizations should apply patches as soon as they are released by Grandstream to mitigate this vulnerability. Regularly updating firmware is essential to protect devices from known vulnerabilities. If a patch is unavailable, consider implementing network controls to limit device exposure.
For more information on remediation strategies and security practices, organizations can refer to the best practices in penetration testing and ensure proper configuration hardening.
Detection Guidance
To detect potential exploitation of this vulnerability, organizations should monitor logs for unusual access patterns to the /cgi-bin/api.values.get endpoint. Behavioral anomalies and network signatures indicative of buffer overflow attacks should also be scrutinized.
AppSecure Threat Intelligence Insight
The long-term significance of CVE-2026-2329 highlights the ongoing challenges in securing IoT devices, particularly in the VoIP sector. This vulnerability may represent a trend toward increasing vulnerabilities that allow remote exploitation without authentication.
Security teams should recognize the patterns of vulnerabilities that may arise from inadequate input validation in network-accessible applications. This incident serves as a strategic reminder for implementing robust security measures during the development and deployment phases.
For further insights into mitigating similar vulnerabilities, organizations should explore the following resources: penetration testing methodology and the importance of continuous security assessments.
Additionally, organizations should stay informed about trends in vulnerability exposure, as seen in resources like the vulnerability management program to better understand how to protect against future threats.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
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