CVE-2025-61917 is a vulnerability identified in the open source workflow automation platform n8n, specifically affecting versions from 1.65.0 up to but not including 1.114.3. The root cause is the use of Node.js Buffer.allocUnsafe() and Buffer.allocUnsafeSlow() functions within the n8n task runner. These functions allocate memory buffers without initializing them, meaning the buffers may contain leftover data from previous operations within the same Node.js process. Because n8n executes user-defined workflows and tasks, untrusted or semi-trusted code can trigger allocation of these uninitialized buffers, potentially exposing residual sensitive information such as secrets, tokens, or data from prior requests. This represents a classic case of CWE-668 (Exposure of Resource to Wrong Sphere) and CWE-200 (Information Exposure). The vulnerability does not require user interaction but does require low-level privileges within the n8n environment. The CVSS v3.1 score is 7.7 (high), reflecting the network attack vector, low attack complexity, required privileges, no user interaction, and a scope change with high confidentiality impact but no integrity or availability impact. No known exploits are reported in the wild as of the publication date. The issue was patched in n8n version 1.114.3 by replacing unsafe buffer allocation with safe alternatives that zero-initialize memory, preventing leakage of residual data. Organizations running affected versions should prioritize upgrading and reviewing workflow configurations to minimize exposure of sensitive data.

For European organizations, this vulnerability poses a significant risk of sensitive data leakage from automated workflows managed by n8n. Since n8n is used to orchestrate business-critical processes, exposure of secrets, tokens, or confidential data could lead to unauthorized access to internal systems, data breaches, or compliance violations under regulations such as GDPR. The confidentiality impact is high, as attackers with low privileges can access residual memory contents without needing user interaction. While integrity and availability are not directly affected, the leakage of sensitive information can facilitate further attacks or espionage. Organizations in sectors with stringent data protection requirements, such as finance, healthcare, and government, are particularly vulnerable. The risk is amplified if n8n is exposed to external networks or integrated with cloud services. Failure to patch promptly could result in exploitation by threat actors seeking to harvest credentials or sensitive workflow data.

1. Upgrade all n8n instances to version 1.114.3 or later immediately to apply the patch that replaces unsafe buffer allocation with safe, zero-initialized buffers. 2. Conduct a thorough audit of workflows and tasks to identify any that handle sensitive data, ensuring that secrets and tokens are stored and transmitted securely using n8n's credential management features. 3. Restrict access to the n8n environment to trusted users and networks, minimizing the risk of low-privilege attackers exploiting the vulnerability. 4. Implement runtime monitoring and logging to detect unusual access patterns or data exfiltration attempts related to workflow executions. 5. If upgrading immediately is not possible, consider isolating n8n instances in segmented network zones and applying strict access controls to reduce exposure. 6. Review and update incident response plans to include scenarios involving potential data leakage from workflow automation platforms. 7. Educate developers and administrators about secure coding and configuration practices within n8n to prevent introduction of similar vulnerabilities.