CVE-2025-8262 is a vulnerability identified in the yarnpkg Yarn package manager, specifically affecting versions from 1.22.0 through 1.22.22. The issue resides in the function explodeHostedGitFragment within the file src/resolvers/exotics/hosted-git-resolver.js. The vulnerability is characterized by inefficient regular expression complexity, which can be exploited remotely without requiring user interaction or elevated privileges. This inefficiency can lead to excessive CPU consumption when processing crafted input, resulting in a denial-of-service (DoS) condition. The vulnerability has a CVSS 4.0 base score of 5.3, indicating a medium severity level. The attack vector is network-based (AV:N), with low attack complexity (AC:L), no privileges required (PR:L), and no user interaction needed (UI:N). The impact primarily affects availability (VA:L), with no direct confidentiality or integrity impact. The vulnerability does not involve scope changes or other impact categories. A patch has been identified (commit 97731871e674bf93bcbf29e9d3258da8685f3076) to address this issue, and applying this patch is recommended to mitigate the risk. No known exploits are currently reported in the wild. The vulnerability arises from the inefficient handling of regular expressions, which can be triggered by maliciously crafted inputs targeting the hosted-git resolver component, potentially causing resource exhaustion and service disruption in environments using the affected Yarn versions.

For European organizations, the impact of CVE-2025-8262 can be significant in environments where Yarn is used extensively for JavaScript package management, particularly in development, continuous integration/continuous deployment (CI/CD) pipelines, and production build systems. The vulnerability could be exploited remotely to cause denial-of-service conditions, leading to service outages or degraded performance of build and deployment processes. This disruption can delay software delivery, impact operational efficiency, and potentially affect customer-facing applications if the build or deployment pipelines are interrupted. Organizations relying on automated dependency resolution and package management with vulnerable Yarn versions may face increased risk of operational downtime. Additionally, if exposed in publicly accessible environments or developer workstations connected to corporate networks, the vulnerability could be leveraged as part of a broader attack chain. Although the vulnerability does not directly compromise data confidentiality or integrity, the availability impact can indirectly affect business continuity and service reliability. European organizations with stringent uptime requirements or those operating critical infrastructure may find this vulnerability particularly concerning.

To mitigate CVE-2025-8262, European organizations should take the following specific actions: 1) Immediately identify all instances of Yarn versions 1.22.0 through 1.22.22 in use across development, testing, and production environments. 2) Apply the official patch referenced by commit 97731871e674bf93bcbf29e9d3258da8685f3076 or upgrade to a fixed Yarn version beyond 1.22.22 that includes the remediation. 3) Implement input validation and sanitization controls where possible to detect and block maliciously crafted inputs targeting the hosted-git resolver functionality. 4) Monitor resource usage patterns on systems running Yarn to detect anomalous CPU spikes indicative of exploitation attempts. 5) Restrict network exposure of systems running vulnerable Yarn instances, especially those accessible from untrusted networks, to reduce remote attack surface. 6) Integrate vulnerability scanning and dependency management tools into CI/CD pipelines to automatically detect and remediate vulnerable Yarn versions. 7) Educate development and operations teams about the risks of inefficient regular expression vulnerabilities and encourage best practices in dependency management. These targeted measures go beyond generic advice by focusing on patch management, exposure reduction, and proactive monitoring specific to this vulnerability's characteristics.