CVE-2026-81357 in Visual Studio Code
Summary
by MITRE • 09/09/2026
Server-side request forgery (ssrf) in Visual Studio Code allows an unauthorized attacker to bypass a security feature over a network.
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Analysis
by VulDB Data Team • 09/09/2026
The vulnerability identified as Server-Side Request Forgery, or SSRF, within Microsoft Visual Studio Code represents a significant security flaw that compromises the integrity of the development environment by allowing external actors to manipulate internal server behavior. This specific class of attack exploits the application's ability to make network requests on behalf of the user without adequately validating the destination addresses or protocols involved. In this context, an unauthorized attacker can leverage maliciously crafted inputs within VS Code extensions or workspace configurations to force the integrated development environment to initiate connections to arbitrary resources located either inside the local network perimeter or in cloud environments that would otherwise be inaccessible from the public internet. The core technical flaw lies in the insufficient sanitization of user-supplied data before it is processed by internal HTTP clients, which permits the injection of malicious URLs targeting localhost interfaces, metadata services on virtual machines, or other sensitive backend systems.
From an operational perspective, this vulnerability enables a wide range of detrimental outcomes depending on the network topology and the privileges under which Visual Studio Code is executing. An attacker who successfully exploits this SSRF condition can potentially access internal APIs, retrieve configuration files containing secrets such as API keys or database credentials, or interact with management interfaces for container orchestration platforms like Kubernetes or Docker that are exposed locally. Furthermore, if the development machine has access to cloud provider metadata endpoints, typically found at addresses like 169.254.169.254, the attacker could extract instance identity documents and temporary security credentials, thereby escalating their foothold from a local code editor compromise to full control over associated cloud infrastructure. This bypasses standard network segmentation strategies because the request originates from within the trusted zone of the developer's machine rather than from an external source.
The classification of this vulnerability aligns with Common Weakness Enumeration identifier CWE-918, which specifically addresses Server-Side Request Forgery (SSRF) flaws where a server makes requests based on user input without proper validation. Additionally, in terms of tactical execution within the MITRE ATT&CK framework for enterprise security, this behavior maps to techniques involving Taint Analysis and potentially Data from Cloud Services if cloud metadata is targeted. The attack vector typically involves social engineering or code injection through compromised extensions, requiring initial access but no physical presence on the machine once executed. This highlights a critical gap in how development tools handle trust boundaries between user-provided content and system-level network operations.
To mitigate this risk, organizations must ensure that Visual Studio Code is updated to the latest stable release where Microsoft has implemented stricter validation logic for internal requests. Developers should avoid installing extensions from untrusted sources and regularly audit installed plugins for known vulnerabilities. Network administrators can implement egress filtering rules on firewalls or proxy servers to restrict outbound connections from development workstations, particularly blocking access to non-standard ports and private IP ranges that are not required for legitimate software updates or package management. Furthermore, enabling strict Content Security Policies within the editor's configuration and disabling unnecessary features such as remote SSH tunnels when not in use can reduce the attack surface available to potential SSRF exploiters.