CVE-2018-6337

Name: CVE-2018-6337
Creator: NVD / NIST
Published: 2018-12-31T22:29:00.247+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 1.78%

Last modified Jun 17, 2026

CVE-2018-6337 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. 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. EPSS estimates a 1.78% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

EPSS Probability

1.78%

75.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Facebook	Folly	>= 2017.12.11.00, <= 2018.08.09.00
Facebook	Hhvm	>= 3.26, < 3.26.3

References

https://github.com/facebook/folly/commit/8e927ee48b114c8a2f90d0cbd5ac753795a6761fPatch, Third Party Advisory
https://github.com/facebook/hhvm/commit/e2d10a1e32d01f71aaadd81169bcb9ae86c5d6b8Patch, Third Party Advisory
https://hhvm.com/blog/2018/05/24/hhvm-3.26.3.htmlRelease Notes, Vendor Advisory
https://github.com/facebook/folly/commit/8e927ee48b114c8a2f90d0cbd5ac753795a6761fPatch, Third Party Advisory
https://github.com/facebook/hhvm/commit/e2d10a1e32d01f71aaadd81169bcb9ae86c5d6b8Patch, Third Party Advisory
https://hhvm.com/blog/2018/05/24/hhvm-3.26.3.htmlRelease Notes, Vendor Advisory

Timeline

Published: Dec 31, 2018
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2018-6337?

How severe is CVE-2018-6337?

CVE-2018-6337 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 1.78% probability of exploitation in the next 30 days.

How do I fix CVE-2018-6337?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2018-6337?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST