Software Engineering Institute

CWE-124: Buffer Underwrite ('Buffer Underflow') - CVE-2018-5388

In stroke_socket.c, a missing packet length check could allow a buffer underflow, which may lead to resource exhaustion and denial of service while reading from the socket.

According to the vendor, an attacker must typically have local root permissions to access the socket. However, other accounts and groups such as the vpn group (if capability dropping in enabled, for example) may also have sufficient permissions, but this configuration does not appear to be the default behavior.

A remote attacker with local user credentials (possibly a normal user in the vpn group, or root) may be able to underflow the buffer and cause a denial of service.

Apply an update

StrongSwan version 5.6.3 and above contain a patch for this issue.