Vulnerability record · CVE-2018-6337 · published 31 December 2018

CVE-2018-6337: Facebook folly memory buffer overflow vulnerability

Facebook · Folly

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.

7.5 CVSS 3.1 High EPSS 1.8% · top 22.7% CWE-212 · CWE-212CWE-119 · Memory buffer overflow

7.5CVSS 3.1 base score, v2 5.0

1.8%EPSS exploitation probability, 30 days

NoNot in CISA KEV

2Affected product versions listed by NVD

6References

17 Jun 2026Last modified by NVD

Description

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

Affected products

2 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

Folly Facebook

Hhvm Facebook

References

Link	Tags
https://github.com/facebook/folly/commit/8e927ee48b114c8a2f90d0cbd5ac753795a6761f	PatchThird Party Advisory
https://github.com/facebook/hhvm/commit/e2d10a1e32d01f71aaadd81169bcb9ae86c5d6b8	PatchThird Party Advisory
https://hhvm.com/blog/2018/05/24/hhvm-3.26.3.html	Release NotesVendor Advisory
https://github.com/facebook/folly/commit/8e927ee48b114c8a2f90d0cbd5ac753795a6761f	PatchThird Party Advisory
https://github.com/facebook/hhvm/commit/e2d10a1e32d01f71aaadd81169bcb9ae86c5d6b8	PatchThird Party Advisory
https://hhvm.com/blog/2018/05/24/hhvm-3.26.3.html	Release NotesVendor Advisory

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Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2018-6337), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.