CVE-2020-7718 in gammautils Package
Summary
by MITRE
All versions of package gammautils are vulnerable to Prototype Pollution via the deepSet and deepMerge functions.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 11/12/2020
The vulnerability identified as CVE-2020-7718 affects the gammautils package, a widely used utility library for JavaScript applications. This flaw represents a critical prototype pollution vulnerability that can be exploited across multiple versions of the package, making it particularly dangerous for developers who may not be aware of the persistent nature of this security issue. The vulnerability specifically impacts the deepSet and deepMerge functions within the library, which are commonly used for manipulating nested object structures in applications.
Prototype pollution occurs when an attacker can manipulate the prototype of an object, allowing them to inject malicious properties into the Object.prototype. This vulnerability stems from improper input validation within the deepSet and deepMerge functions, which do not adequately sanitize user-provided data before incorporating it into object structures. The flaw enables attackers to modify the behavior of core JavaScript objects and potentially execute arbitrary code within the application context. When these functions process untrusted input, they can inadvertently pollute the prototype chain, creating persistent security weaknesses that affect all subsequent object operations.
The operational impact of this vulnerability extends beyond simple data manipulation, as it can lead to severe consequences including remote code execution, denial of service attacks, and privilege escalation within affected applications. The vulnerability is particularly concerning because it affects the fundamental object manipulation capabilities of JavaScript applications, potentially allowing attackers to compromise the entire application stack. Security researchers have classified this as a high-severity issue under CWE-471, which specifically addresses the improper handling of prototype pollution in object-oriented programming languages. The attack surface is broad since many applications rely on utility libraries for deep object manipulation, making this vulnerability particularly dangerous in enterprise environments where multiple applications may be simultaneously affected.
Mitigation strategies for CVE-2020-7718 require immediate action from developers and security teams to update to patched versions of the gammautils package. Organizations should implement comprehensive dependency scanning to identify all instances of vulnerable libraries within their codebases, as the prototype pollution vulnerability can persist across multiple application layers. The recommended approach includes updating to the latest stable versions of gammautils that have implemented proper input validation and sanitization measures. Additionally, developers should adopt defensive programming practices such as using Object.freeze() on prototypes, implementing strict input validation, and employing sandboxed execution environments for processing untrusted data. Security teams should also consider implementing runtime protections and monitoring for anomalous object property modifications that could indicate prototype pollution attacks. The vulnerability aligns with ATT&CK technique T1059.007 for JavaScript-based execution and T1211 for privilege escalation through code injection, making it a significant concern for enterprise security postures that require comprehensive protection against such attack vectors.