The vulnerability in PEVANS Socket versions prior to 2.041 arises from incorrect length checking in the pack_ip_mreq_source() function within Socket.xs. The function checks the length of the source argument using the byte length from a preceding multiaddr argument, which is always 4 bytes. Consequently, a source argument shorter than 4 bytes is not properly rejected, causing the function to copy up to 3 bytes beyond the source buffer into the imr_sourceaddr field. This results in an out-of-bounds heap read, potentially exposing adjacent heap memory contents.

This vulnerability allows an attacker to cause an out-of-bounds read on the heap, potentially leaking sensitive memory contents. The CVSS score of 9.1 indicates a critical severity with high confidentiality impact and high availability impact, but no integrity impact. There are no known exploits in the wild as of the published date.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or workaround has been published. Users should monitor vendor communications for updates and avoid passing source arguments shorter than 4 bytes to the affected function as a temporary precaution if feasible.