CVE-2026-66404

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 ImpactpartialSuccessful exploitation gives limited 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

0.20% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 10.1% of scored records. A rank, not a probability.

NVD base score

6.0 (CVSS v4.0), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

NVD analysis status

Deferred. NVD last modified this record on 2026-08-28.

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

2026-08-10 07:59Z2 MO AGO

Last updated

2026-08-10 17:47Z2 MO AGO

Reserved

2026-07-27

Assigning CNA

jpcert

Record state

PUBLISHED

Severity

Medium (CVSS 6.0)

CNA CVSS vector

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N

Weaknesses

• CWE-295Improper Certificate ValidationBase

Data version

5.2

Document digest

60a6678131ab72d1bcc7fe1b9fb88c976b5f1bc71dd0e5a0627f476f7e573c08

• robot.hellohas.co.jphttps://robot.hellohas.co.jp/news/update_20260331/
• jvn.jphttps://jvn.jp/en/vu/JVNVU92804348/