CVE-2026-2577 is a critical security vulnerability identified in the HKUDS nanobot product, specifically within its WhatsApp bridge component. The flaw arises because the WebSocket server is bound to all network interfaces (0.0.0.0) on port 3001 by default and does not enforce any authentication for incoming connections. This design oversight corresponds to CWE-306, 'Missing Authentication for Critical Function.' An attacker with network access to the bridge can connect unauthenticated to the WebSocket server, effectively hijacking the WhatsApp session. This hijacking allows the attacker to send messages impersonating the legitimate user, intercept all incoming messages and media in real-time, and capture authentication QR codes used for session establishment. The vulnerability has a CVSS v3.1 base score of 10.0, reflecting its critical nature with network attack vector (AV:N), low attack complexity (AC:L), no privileges required (PR:N), no user interaction (UI:N), and complete impact on confidentiality and integrity (C:H/I:H) but no impact on availability (A:N). The scope is changed (S:C), indicating the vulnerability affects resources beyond the initially vulnerable component. No patches or mitigations have been published at the time of disclosure, and no known exploits are reported in the wild. This vulnerability poses a severe risk to any deployment of nanobot that exposes the WhatsApp bridge component to accessible networks without additional protections.

For European organizations, the impact of this vulnerability is substantial. WhatsApp is widely used across Europe for both personal and business communications, including in sectors such as finance, healthcare, and government. The ability for an attacker to hijack WhatsApp sessions can lead to unauthorized disclosure of sensitive communications, impersonation of users to conduct social engineering or fraud, and interception of confidential media. This can result in reputational damage, regulatory penalties under GDPR due to data breaches, and operational disruptions. Organizations relying on nanobot for WhatsApp integration or automation are particularly vulnerable if the bridge component is exposed to untrusted networks. The lack of authentication means that even internal network threats or compromised devices on the same network segment can exploit this vulnerability. The critical severity and ease of exploitation increase the urgency for European entities to address this risk promptly.

To mitigate this vulnerability effectively, organizations should immediately restrict network access to the nanobot WhatsApp bridge WebSocket server on port 3001. This can be achieved by implementing strict firewall rules or network segmentation to ensure only trusted hosts can connect. Deploying VPNs or zero-trust network access controls to limit exposure is recommended. If possible, disable the WhatsApp bridge component until a vendor patch or update is available. Monitor network traffic for unexpected connections to port 3001 and unusual WhatsApp session activity indicative of hijacking attempts. Implement intrusion detection or prevention systems with signatures tailored to detect unauthorized WebSocket connections. Additionally, organizations should engage with HKUDS to obtain patches or updates addressing this vulnerability and apply them promptly once available. Educate users about the risks of session hijacking and encourage the use of multi-factor authentication on WhatsApp accounts where supported. Finally, conduct regular security audits of nanobot deployments to verify that no unintended exposure exists.