What’s Vulnerable › Vulnerabilities

CVE-2017-0904

• Severity: high (CVSS 8.1 v3.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 2.4% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2017-11-13 · updated 2026-06-17
• Weakness: CWE-242

Description

The private_address_check ruby gem before 0.4.0 is vulnerable to a bypass due to use of Ruby's Resolv.getaddresses method, which is OS-dependent and should not be relied upon for security measures, such as when used to blacklist private network addresses to prevent server-side request forgery.

Affected products

• HackerOne private_address_check ruby gem: before 0.4.0 — fixed in 0.4.0

How to fix

Upgrade to a fixed version: HackerOne private_address_check ruby gem 0.4.0. Check the vendor advisory for mitigations.

References

• https://edoverflow.com/2017/ruby-resolv-bug/
• https://github.com/jtdowney/private_address_check/commit/58a0d7fe31de339c0117160567a5b33ad82b46af
• https://github.com/jtdowney/private_address_check/issues/1
• https://hackerone.com/reports/287245
• https://hackerone.com/reports/287835
• https://edoverflow.com/2017/ruby-resolv-bug/
• https://github.com/jtdowney/private_address_check/commit/58a0d7fe31de339c0117160567a5b33ad82b46af
• https://github.com/jtdowney/private_address_check/issues/1
• https://hackerone.com/reports/287245
• https://hackerone.com/reports/287835

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