CVE-2018-6337
CVE-2018-6337 is a high-severity vulnerability in Facebook Folly with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-119.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 5.0
- EPSS exploit prediction: 2% (78th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-119
- Affected product: Facebook Folly
- Published:
- Last modified:
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.
Frequently asked questions
- What is CVE-2018-6337?
- 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.
- How severe is CVE-2018-6337?
- CVE-2018-6337 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
- Is CVE-2018-6337 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2018-6337?
- CVE-2018-6337 primarily affects Facebook Folly. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2018-6337?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2018-6337 published?
- CVE-2018-6337 was published on 2018-12-31 and last updated on 2026-06-17.
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
Affected products (2)
- cpe:2.3:a:facebook:folly:*:*:*:*:*:*:*:*
- cpe:2.3:a:facebook:hhvm:*:*:*:*:*:*:*:*
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