CVE-2024-35266 is a high-severity vulnerability classified under CWE-79, which pertains to improper neutralization of input during web page generation, commonly known as Cross-site Scripting (XSS). This vulnerability affects Microsoft Azure DevOps Server 2022, specifically version 20231128.1. The issue arises when the server improperly sanitizes user-supplied input, allowing an attacker with limited privileges (requires low privileges and user interaction) to inject malicious scripts into web pages generated by the server. When other users view these pages, the malicious scripts execute in their browsers, potentially leading to credential theft, session hijacking, or unauthorized actions performed on behalf of the victim. The CVSS v3.1 score of 7.6 reflects a high severity, with an attack vector of network (remote exploitation), low attack complexity, requiring privileges and user interaction, and resulting in high confidentiality and integrity impacts, with low availability impact. No known exploits are currently reported in the wild, but the vulnerability is publicly disclosed and patched versions are expected. The vulnerability's scope is unchanged, meaning the impact is limited to the vulnerable component without affecting other system components. The vulnerability is significant because Azure DevOps Server is widely used for software development lifecycle management, including source code repositories, build automation, and deployment pipelines, making it a valuable target for attackers aiming to compromise development environments or inject malicious code into software supply chains.

For European organizations, the impact of this vulnerability can be substantial. Azure DevOps Server is commonly used by enterprises for managing software development and deployment processes. Exploitation of this XSS vulnerability could allow attackers to steal credentials or session tokens of developers and administrators, leading to unauthorized access to source code repositories and build pipelines. This could result in code tampering, insertion of backdoors, or disruption of software delivery. Confidentiality breaches could expose sensitive intellectual property and business-critical information. Integrity impacts could compromise the trustworthiness of software artifacts produced by the organization, potentially affecting downstream customers and partners. Availability impact is low but could arise indirectly if attackers leverage stolen credentials to cause further damage. Given the reliance on Azure DevOps in regulated sectors such as finance, healthcare, and critical infrastructure within Europe, exploitation could also lead to compliance violations under GDPR and other data protection regulations, resulting in legal and financial penalties.

European organizations should prioritize patching Azure DevOps Server installations to the latest version as soon as Microsoft releases a fix for CVE-2024-35266. Until patches are available, organizations should implement strict input validation and output encoding on any custom extensions or integrations with Azure DevOps Server to reduce the risk of XSS. Employ Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts in browsers accessing the server. Limit user privileges to the minimum necessary, especially for users who can input data into web pages, to reduce the attack surface. Monitor logs for unusual activity that may indicate exploitation attempts, such as unexpected script injections or anomalous user behavior. Conduct security awareness training for developers and administrators to recognize phishing or social engineering attempts that could facilitate exploitation. Additionally, consider isolating Azure DevOps Server environments and restricting network access to trusted users and IP ranges to reduce exposure.