CVE-2018-3759: Private Address Check Project Private Address Check

Low severity, CVSS 3.7. EPSS: 0.7% chance of exploitation in the next 30 days.

private_address_check ruby gem before 0.5.0 is vulnerable to a time-of-check time-of-use (TOCTOU) race condition due to the address the socket uses not being checked. DNS entries with a TTL of 0 can trigger this case where the initial resolution is a public address but the subsequent resolution is a private address.

Affected products

• Private Address Check Project Private Address Check: before 0.5.0 (fixed in 0.5.0)

Published 2018-06-13. Last modified 2026-06-17.