CVE-2026-66402

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.
• AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
• 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

0.34% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 27.1% of scored records. A rank, not a probability.

NVD base score

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

NVD CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/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

Analyzed. NVD last modified this record on 2026-10-02.

Red Hat severity

Moderate. Red Hat's rating for its own products, not a CVSS rating.

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

2026-08-01 12:22Z2 MO AGO

Last updated

2026-08-05 03:56Z2 MO AGO

Reserved

2026-07-26

Assigning CNA

VulnCheck

Record state

PUBLISHED

Severity

Critical (CVSS 9.3)

CNA CVSS vector

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

Weaknesses

• CWE-295Improper Certificate ValidationBase
• CWE-222Truncation of Security-relevant InformationBase

Data version

5.2

Document digest

afaa63434f379cab61dd889b28f8d29fe369aa692b9e0f464f304c1d4d63ad6a

• github.comGitHub Security Advisory (GHSA-43hh-p3vw-hfx3)https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-43hh-p3vw-hfx3vendor-advisory
• github.comPatch Commithttps://github.com/FreeRDP/FreeRDP/commit/b9533f07f98c25ed01c5f543b4d0ce73e120f5fdpatch
• www.vulncheck.comVulnCheck Advisory: FreeRDP before 3.29.0 TLS Certificate Identity Validation Bypasshttps://www.vulncheck.com/advisories/freerdp-before-tls-certificate-identity-validation-bypassthird-party-advisory