CVE-2025-57326 is a Prototype Pollution vulnerability identified in the byGroupAndType function of the sassdoc-extras package, version 2.5.1 and earlier. Prototype Pollution vulnerabilities occur when an attacker is able to inject or modify properties on the Object.prototype, which is the base object from which all JavaScript objects inherit. By manipulating this prototype, an attacker can influence the behavior of all objects in the environment, potentially causing unexpected behavior or security issues. In this specific case, the vulnerability allows an attacker to supply a crafted payload that injects properties into Object.prototype. The primary consequence of this injection is a denial of service (DoS) condition, which can disrupt the normal operation of applications relying on sassdoc-extras. The vulnerability has a CVSS v3.1 base score of 7.5, indicating a high severity level. The vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) shows that the attack can be performed remotely over the network without any privileges or user interaction, and it impacts availability only, without affecting confidentiality or integrity. No known exploits are currently reported in the wild, and no patches or fixes have been linked yet. The vulnerability is categorized under CWE-1321, which relates to improper handling of prototype pollution issues in JavaScript environments. Since sassdoc-extras is a tool used in documentation generation for Sass projects, this vulnerability could affect development and build pipelines that incorporate this package, potentially causing build failures or service interruptions.

For European organizations, the impact of CVE-2025-57326 primarily revolves around disruption of development and deployment workflows that utilize sassdoc-extras. Organizations heavily reliant on automated documentation generation for Sass-based projects may experience denial of service conditions during build or documentation generation processes, leading to delays in software delivery and potential operational downtime. While this vulnerability does not directly compromise data confidentiality or integrity, the availability impact can affect continuous integration/continuous deployment (CI/CD) pipelines, developer productivity, and potentially delay time-sensitive releases. Industries with stringent compliance and operational uptime requirements, such as financial services, healthcare, and critical infrastructure sectors in Europe, may find such disruptions particularly impactful. Additionally, organizations that integrate sassdoc-extras into publicly accessible services or developer tools could face indirect reputational damage if service interruptions occur. Since exploitation requires no privileges or user interaction and can be triggered remotely, the risk of automated or widespread exploitation attempts exists once exploit code becomes available, increasing the urgency for mitigation in European enterprises with active use of this package.

Given the absence of an official patch at the time of this report, European organizations should take immediate steps to mitigate the risk posed by CVE-2025-57326. First, conduct an inventory of development and build environments to identify usage of sassdoc-extras version 2.5.1 or earlier. If feasible, temporarily remove or replace sassdoc-extras with alternative documentation tools that do not exhibit this vulnerability. Implement strict input validation and sanitization on any user-supplied data that may interact with the byGroupAndType function to reduce the risk of malicious payload injection. Employ runtime monitoring and anomaly detection within build systems to detect unusual behavior or crashes indicative of exploitation attempts. Restrict network access to build and documentation generation servers to trusted internal networks to limit exposure. Additionally, maintain close monitoring of official sassdoc-extras repositories and security advisories for patches or updates addressing this vulnerability, and apply them promptly once available. Incorporating dependency scanning tools into CI/CD pipelines can help detect vulnerable versions early and prevent deployment of affected packages. Finally, educate development teams about prototype pollution risks and secure coding practices to minimize similar vulnerabilities in custom code.