CVE-2016-10686 in fis-sass-all
Summary
by MITRE
fis-sass-all is another libsass wrapper for node. fis-sass-all downloads binary resources over HTTP, which leaves it vulnerable to MITM attacks. It may be possible to cause remote code execution (RCE) by swapping out the requested resources with an attacker controlled copy if the attacker is on the network or positioned in between the user and the remote server.
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Analysis
by VulDB Data Team • 03/21/2023
The vulnerability identified as CVE-2016-10686 affects fis-sass-all, a libsass wrapper for node.js that facilitates sass compilation within javascript environments. This tool operates by downloading binary resources over unencrypted HTTP connections, creating a significant security exposure that directly violates fundamental security principles outlined in cybersecurity frameworks such as NIST SP 800-53 and ISO/IEC 27001. The core technical flaw lies in the absence of secure transport mechanisms during resource retrieval, specifically the reliance on HTTP rather than HTTPS for downloading binary dependencies.
The operational impact of this vulnerability extends beyond simple data interception, as it creates a pathway for man-in-the-middle attacks that could result in remote code execution. When an attacker successfully intercepts the HTTP traffic between the node.js application and the remote server hosting the binary resources, they can replace the legitimate binaries with malicious copies that execute arbitrary code on the victim's system. This represents a critical security weakness that aligns with CWE-319, which specifically addresses the exposure of sensitive information through improper use of network protocols. The vulnerability directly enables attack patterns described in the MITRE ATT&CK framework under T1059.007 for remote code execution and T1566 for phishing attacks that leverage network infiltration.
The risk assessment for this vulnerability is particularly concerning given that fis-sass-all operates in development environments where developers often work on untrusted networks such as public Wi-Fi or corporate networks with insufficient network security controls. The attack vector requires only that the attacker be positioned within the network path between the vulnerable application and its remote resource servers, making it exploitable in common network scenarios. This makes the vulnerability particularly dangerous as it does not require sophisticated attack infrastructure or specific network conditions beyond basic network access. The potential for supply chain compromise increases significantly when considering that many development tools rely on similar insecure download mechanisms, creating a broader ecosystem vulnerability that affects multiple applications and development workflows. Organizations implementing security controls should consider this vulnerability as part of their broader application security posture assessment and ensure that all development toolchains implement secure download mechanisms with proper certificate validation and integrity checking.
Mitigation strategies for CVE-2016-10686 should prioritize immediate implementation of HTTPS-based resource retrieval and certificate validation mechanisms. Development teams should migrate from fis-sass-all to more secure alternatives that implement proper transport layer security, such as sass-loader or other sass compilation tools that use encrypted connections for all external dependencies. The implementation of certificate pinning or strict transport security policies would provide additional protection layers against man-in-the-middle attacks. Organizations should also consider implementing network-level controls such as SSL inspection and traffic monitoring to detect and prevent unauthorized modifications to network traffic. Regular security audits of development toolchains and dependency management processes should be conducted to identify similar vulnerabilities in other components of the software supply chain, ensuring comprehensive protection against similar attack vectors that exploit insecure network communications and weak cryptographic practices.