Data::PubSub::Shared components prior to version 0.07 create a memory‑mapped backing file with permissions 0644 by default, making the IPC payload readable by any local user. The creation routine omits the O_NOFOLLOW flag, allowing a malicious user to replace the file path with a symbolic link to a target of their choice and the O_EXCL flag, enabling a pre‑creation race. As a result, local attackers can read or tamper with inter‑process communication data, compromising confidentiality and potentially injecting malicious payloads. The likely attack vector is local user and does not require network access, so the threat is confined to the host where the application runs.

The affected vendor is EGOR and the product is Data::PubSub::Shared. Versions prior to 0.07 are vulnerable; starting with 0.07 the module creates the backing file with mode 0600 and uses O_EXCL and O_NOFOLLOW to mitigate the risk.

The CVSS score of 3.8 indicates low overall severity, and the EPSS score of less than 1% suggests low probability of exploitation. The vulnerability is not catalogued in the CISA KEV list. However, any local user with filesystem access to the shared directory (typically /tmp or /dev/shm) could exploit the weakness, so the actual risk depends on the local privilege model. Because the exposure allows read and possible overwrite of shared data, the impact on confidentiality is significant for sensitive applications, though the requirement of local access limits widespread exploitation.