CVE-2020-7739 in phantomjs-seo
Summary
by MITRE • 10/06/2020
This affects all versions of package phantomjs-seo. It is possible for an attacker to craft a url that will be passed to a PhantomJS instance allowing for an SSRF attack.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 11/16/2020
The vulnerability identified as CVE-2020-7739 represents a critical server-side request forgery flaw within the phantomjs-seo package ecosystem. This security weakness affects all versions of the package and stems from improper input validation mechanisms that fail to adequately sanitize user-provided URLs before processing them through PhantomJS rendering engine. The vulnerability creates a pathway for malicious actors to manipulate the application's behavior by crafting specially crafted URLs that bypass normal security boundaries and potentially access internal resources that should remain isolated from external requests.
The technical implementation of this vulnerability resides in the package's handling of URL parameters that are subsequently passed to PhantomJS instances without proper sanitization or validation. When an attacker constructs a malicious URL containing crafted parameters, these inputs are directly fed into the PhantomJS rendering process, enabling the execution of unauthorized network requests against internal systems. This flaw operates at the intersection of improper input validation and inadequate access control mechanisms, creating a scenario where the application becomes an unwitting proxy for malicious network reconnaissance and data exfiltration activities. The vulnerability is classified under CWE-918, which specifically addresses server-side request forgery vulnerabilities that enable attackers to manipulate the target of network requests.
The operational impact of CVE-2020-7739 extends beyond simple data theft, as it provides attackers with the capability to perform comprehensive internal network reconnaissance and potentially escalate their privileges within the affected environment. An attacker could leverage this vulnerability to probe internal services, access sensitive databases, or even establish command and control channels through the compromised phantomjs-seo instance. The attack surface is particularly concerning given that PhantomJS instances often run with elevated privileges and may have access to internal network resources that are normally protected from external access. This vulnerability aligns with ATT&CK technique T1071.004, which describes the use of application layer protocol manipulation to bypass security controls and gain unauthorized access to network resources.
Mitigation strategies for CVE-2020-7739 require immediate implementation of input validation and sanitization measures that prevent malicious URLs from being processed by PhantomJS instances. Organizations should implement strict URL validation that filters out potentially dangerous protocols and ensures that all inputs are properly escaped before being passed to the rendering engine. The recommended approach includes implementing a whitelist-based validation system that only permits specific, safe URL formats while rejecting any inputs that contain suspicious patterns or protocols that could enable SSRF attacks. Additionally, network segmentation and access control measures should be implemented to limit the potential damage from successful exploitation attempts. The most effective long-term solution involves migrating away from vulnerable packages or upgrading to versions that have implemented proper input validation mechanisms, as the current vulnerability cannot be fully remediated through configuration changes alone.