What’s Vulnerable › Vulnerabilities

CVE-2018-6337

• Severity: high (CVSS 7.5 v3.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.8% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2018-12-31 · updated 2026-06-17
• Weakness: CWE-212

Description

folly::secureRandom will re-use a buffer between parent and child processes when fork() is called. That will result in multiple forked children producing repeat (or similar) results. This affects HHVM 3.26 prior to 3.26.3 and the folly library between v2017.12.11.00 and v2018.08.09.00.

Affected products

• Facebook folly: from 2017.12.11.00 through 2018.08.09.00
• Facebook HHVM: from 3.26 before 3.26.3 — fixed in 3.26.3

How to fix

Upgrade to a fixed version: Facebook HHVM 3.26.3. Check the vendor advisory for mitigations.

References

• https://github.com/facebook/folly/commit/8e927ee48b114c8a2f90d0cbd5ac753795a6761f
• https://github.com/facebook/hhvm/commit/e2d10a1e32d01f71aaadd81169bcb9ae86c5d6b8
• https://hhvm.com/blog/2018/05/24/hhvm-3.26.3.html
• https://github.com/facebook/folly/commit/8e927ee48b114c8a2f90d0cbd5ac753795a6761f
• https://github.com/facebook/hhvm/commit/e2d10a1e32d01f71aaadd81169bcb9ae86c5d6b8
• https://hhvm.com/blog/2018/05/24/hhvm-3.26.3.html

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