CVE-2025-31987 is a medium-severity vulnerability identified in HCL Software's Connections Docs product, specifically version 2.0.2. The vulnerability is classified under CWE-405, which pertains to asymmetric resource consumption. This issue arises from improper validation of certain uploaded documents, which can lead to excessive consumption of system resources. When exploited, this flaw can cause a denial of service (DoS) condition by exhausting critical resources such as CPU, memory, or disk I/O, thereby degrading or completely disrupting the availability of the Connections Docs service. The vulnerability requires network access (AV:N), has a high attack complexity (AC:H), requires low privileges (PR:L), and user interaction (UI:R) to trigger. The scope remains unchanged (S:U), and the impact is limited to availability (A:H) without affecting confidentiality or integrity. No known exploits are currently reported in the wild, and no patches have been published yet. The vulnerability was reserved in April 2025 and published in August 2025, indicating recent discovery and disclosure. The lack of patches suggests that organizations using this product version remain vulnerable until remediation is available. The vulnerability could be triggered by an authenticated user uploading specially crafted documents that cause the application to consume disproportionate resources during processing or validation, leading to service disruption.

For European organizations utilizing HCL Connections Docs 2.0.2, this vulnerability poses a risk primarily to service availability. Organizations relying on this software for collaboration and document management could experience downtime or degraded performance, impacting business continuity and productivity. The denial of service could disrupt internal workflows, delay project timelines, and affect communication among teams. While confidentiality and integrity are not directly impacted, the operational disruption could have cascading effects, especially in sectors where timely access to collaboration tools is critical, such as finance, healthcare, and government. Additionally, if exploited in a targeted manner, it could serve as a vector for distraction or cover for other malicious activities. The requirement for user interaction and low privilege means that insider threats or compromised user accounts could be leveraged to trigger the DoS, increasing the risk in environments with less stringent access controls or where social engineering is prevalent.

Given the absence of an official patch, European organizations should implement several specific mitigations: 1) Restrict upload permissions to trusted users only and enforce strict authentication and authorization controls to minimize the risk of malicious uploads. 2) Implement file upload validation and filtering at the perimeter or proxy level to detect and block suspicious or malformed documents before they reach Connections Docs. 3) Monitor resource utilization closely on servers running Connections Docs to detect abnormal spikes indicative of exploitation attempts, enabling rapid response and mitigation. 4) Employ rate limiting on document uploads to reduce the risk of resource exhaustion from repeated attempts. 5) Isolate Connections Docs instances in segmented network zones with limited access to critical infrastructure to contain potential DoS impacts. 6) Prepare incident response plans specifically addressing DoS scenarios involving document uploads, including fallback communication channels. 7) Stay updated with HCL Software advisories and apply patches promptly once available. 8) Consider deploying web application firewalls (WAFs) with custom rules to detect and block exploit attempts targeting this vulnerability.