CVE-2018-6340

Exploitation

Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.

SSVC decision

• ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
• AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
• Technical ImpacttotalSuccessful exploitation gives total control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

1.43% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 72.5% of scored records. A rank, not a probability.

NVD base score

8.1 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

NVD analysis status

Modified. NVD last modified this record on 2026-06-17.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2018-12-31 22:00Z7 YR AGO

Last updated

2025-05-06 19:00Z1 YR AGO

Reserved

2018-01-26

Assigning CNA

facebook

Record state

PUBLISHED

Severity

High (CVSS 8.1)

CNA CVSS vector

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

Weaknesses

• CWE-125Out-of-bounds ReadBase

Data version

5.1

Document digest

8b82e6238ca9ccfc2cc99c1aae8fd3f6e53770b5ffd325bdbe516a35d7ead7e3

• hhvm.comhttps://hhvm.com/blog/2018/12/18/hhvm-3.30.1.htmlx_refsource_MISC
• github.comhttps://github.com/facebook/hhvm/commit/4bff3bfbe90d10451e4638c2118d1ad1117bb3e3x_refsource_MISC