The vulnerability in Data::RadixTree::Shared (versions before 0.02) arises from incorrect permission assignment (CWE-732) and unsafe file opening practices (CWE-59). Specifically, the mmap backing file is created with mode 0666, which under default umask results in a world-readable file. The open call lacks O_NOFOLLOW and O_EXCL flags, allowing an attacker to exploit symlink redirection and pre-creation race conditions. Since the shared segment typically resides in shared directories accessible by local users, this can lead to unauthorized local users reading IPC payloads or manipulating the file path to influence the open operation.

Local users can read sensitive IPC payloads stored in the world-readable mmap backing file. Additionally, attackers can exploit symlink redirection and pre-creation race conditions to manipulate the file open operation, potentially leading to unauthorized access or interference with the shared memory segment. This compromises confidentiality and integrity of IPC data on the affected system.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, users should avoid running vulnerable versions in environments where local users are untrusted or can access shared directories such as /tmp or /dev/shm. Restricting permissions on the shared directory or using alternative IPC mechanisms with secure file handling may reduce risk.