CVE-2025-48040 is a vulnerability classified under CWE-400 (Uncontrolled Resource Consumption) and CWE-770 (Allocation of Resources Without Limits or Throttling) affecting the Erlang Open Telecom Platform (OTP), specifically within the ssh and ssh_sftp modules. The vulnerability exists in the ssh_sftpd.erl source file and impacts OTP versions from 17.0 up to 28.0.3, including specific patch versions 27.3.4.3 and 26.2.5.15, and ssh package versions from 3.0.1 through 5.3.3. The vulnerability allows an attacker to cause excessive resource allocation and flooding by exploiting the SSH SFTP server component, potentially leading to denial of service (DoS) conditions. The CVSS v4.0 base score is 6.9 (medium severity), with an attack vector of network (AV:N), low attack complexity (AC:L), no privileges required (PR:N), no user interaction (UI:N), and no impact on confidentiality or integrity but a low impact on availability (VA:L). This means the vulnerability can be exploited remotely without authentication or user interaction, causing resource exhaustion that may degrade or disrupt service availability. No known exploits are currently reported in the wild, and no official patches have been linked yet. The vulnerability is significant because Erlang OTP is widely used in telecommunications, distributed systems, and messaging platforms, where SSH and SFTP are critical for secure file transfers and remote management. Uncontrolled resource consumption can lead to service outages, impacting business continuity and operational reliability.

For European organizations, the impact of CVE-2025-48040 can be substantial, especially for those relying on Erlang OTP-based infrastructure for telecommunications, financial services, and critical infrastructure management. The vulnerability could be exploited to launch denial-of-service attacks that degrade or halt services dependent on SSH/SFTP, affecting data transfers and remote administration. This can disrupt business operations, cause financial losses, and damage reputation. Organizations in sectors such as telecom operators, cloud service providers, and enterprises using Erlang-based messaging or IoT platforms are particularly at risk. The medium severity rating reflects the lack of confidentiality or integrity compromise but highlights availability risks that can cascade into broader operational impacts. Given the remote, unauthenticated exploitability, attackers can target exposed SSH services without needing credentials, increasing the attack surface. In Europe, where strict regulatory frameworks like GDPR mandate service availability and data protection, such disruptions could lead to compliance issues and penalties if service outages affect customer data processing or critical services.

1. Immediate mitigation should include monitoring and restricting access to SSH/SFTP services running on Erlang OTP instances, using network-level controls such as firewalls and intrusion prevention systems to limit exposure to untrusted networks. 2. Implement rate limiting and connection throttling on SSH/SFTP endpoints to prevent excessive resource consumption from repeated or malformed requests. 3. Deploy anomaly detection tools to identify unusual spikes in SSH/SFTP traffic indicative of exploitation attempts. 4. Upgrade Erlang OTP to versions beyond 28.0.3 once official patches addressing this vulnerability are released by the vendor. 5. In the interim, consider disabling or restricting the ssh_sftp service if it is not essential to reduce the attack surface. 6. Conduct regular security audits and penetration testing focusing on SSH/SFTP services to identify and remediate resource exhaustion risks. 7. Maintain comprehensive logging and alerting on SSH/SFTP resource usage metrics to enable rapid incident response. These steps go beyond generic advice by focusing on network controls, service hardening, and proactive detection tailored to the nature of this vulnerability.