CVE-2025-24831 is a local privilege escalation vulnerability identified in the Acronis Cyber Protect Cloud Agent for Windows, specifically in versions prior to build 39378. The root cause of this vulnerability is an unquoted search path issue, classified under CWE-428. An unquoted search path vulnerability occurs when a software application or service executes programs or scripts using a path that includes spaces but lacks proper quotation marks. This can allow an attacker with local access to place a malicious executable in a directory that is searched earlier in the system's PATH environment variable, causing the system to execute the malicious code with elevated privileges instead of the intended legitimate executable. Since the Acronis Cyber Protect Cloud Agent operates with elevated privileges to perform backup and protection tasks, exploitation of this vulnerability could allow an attacker to escalate from a lower-privileged user account to SYSTEM or administrative privileges on the affected Windows host. This type of vulnerability requires local access to the system, meaning an attacker must already have some level of access to the machine, either through a compromised user account or physical access. There is no indication that user interaction beyond local access is required. Currently, there are no known exploits in the wild targeting this vulnerability, and no patches have been explicitly linked or published at the time of this analysis. The vulnerability affects all unspecified versions of the Acronis Cyber Protect Cloud Agent before build 39378 on Windows platforms. Given the nature of the vulnerability, it primarily impacts the confidentiality, integrity, and availability of the affected system by enabling privilege escalation, which could lead to full system compromise if exploited successfully.

For European organizations, the impact of CVE-2025-24831 can be significant, especially for those relying on Acronis Cyber Protect Cloud Agent for backup and cybersecurity protection. Successful exploitation could allow attackers to gain administrative control over critical backup infrastructure, potentially leading to unauthorized data access, tampering with backup data, or disabling backup services. This could severely affect data integrity and availability, undermining business continuity and disaster recovery capabilities. Organizations in sectors with stringent data protection requirements, such as finance, healthcare, and government, may face regulatory and compliance risks if backups are compromised. Additionally, since the vulnerability requires local access, it could be leveraged as part of a multi-stage attack where an initial foothold is established through phishing or other means, followed by privilege escalation to move laterally within the network. The absence of known exploits in the wild currently reduces immediate risk but does not eliminate the potential for future exploitation. Therefore, European organizations using affected versions should prioritize mitigation to prevent escalation scenarios that could lead to broader network compromise.

1. Immediate Upgrade: Organizations should upgrade the Acronis Cyber Protect Cloud Agent to build 39378 or later, where this vulnerability is addressed. 2. Restrict Local Access: Limit local user access to systems running the Acronis agent to trusted personnel only, reducing the risk of an attacker gaining the initial foothold needed to exploit this vulnerability. 3. Environment Hardening: Review and harden the system PATH environment variable and directory permissions to prevent unauthorized placement of executables in directories that are searched before legitimate application paths. 4. Application Whitelisting: Implement application control policies that restrict execution of unauthorized binaries, especially in directories included in the system PATH. 5. Monitoring and Detection: Deploy endpoint detection and response (EDR) solutions to monitor for suspicious activities indicative of privilege escalation attempts, such as unexpected process launches or modifications to system directories. 6. Incident Response Preparation: Prepare and test incident response plans focusing on local privilege escalation scenarios to ensure rapid containment and remediation if exploitation is detected. 7. Vendor Communication: Maintain communication with Acronis for official patches, advisories, and guidance, and apply updates promptly once available.