A path traversal vulnerability in Apache Ant versions prior to 1.10.18 allows malicious servers to overwrite arbitrary files, posing a risk of unauthorized system modification.

This is a relative path traversal vulnerability (CWE-23) occurring in the ftp and scp tasks. An attacker-controlled server can provide malicious paths during a download operation, allowing the software to write files outside the intended destination directory.

By overwriting critical system files or application binaries, an attacker could potentially gain elevated privileges or impair service functionality. While the CVSS score of 7.4 indicates high severity, the requirement for a malicious or intercepted server connection moderates the immediate risk for well-secured environments.

Immediate Action: Upgrade to Apache Ant version 1.10.18 or later, which includes new default protections against writing outside the destination directory.

Proactive Monitoring: Audit build configurations and ensure that server identity checks for scp and ftps tasks are enabled and strictly enforced.

Compensating Controls: Use secure transfer protocols like FTPS or SCP and ensure that all server identity verification settings are strictly configured to prevent man-in-the-middle attacks.

Public Exploit Available: Unknown.

All users of Apache Ant should update to version 1.10.18 immediately to benefit from the new security protections. Organizations should verify that their build pipelines are not bypassing server identity checks, as this is a critical defense against the conditions required to trigger this vulnerability.