Cyber Posture

CVE-2025-66698

HighPublic PoC

Published: 13 January 2026

Published
13 January 2026
Modified
05 February 2026
KEV Added
Patch
CVSS Score 8.6 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
EPSS Score 0.0019 40.8th percentile
Risk Priority 17 60% EPSS · 20% KEV · 20% CVSS

Description

An issue in Semantic machines v5.4.8 allows attackers to bypass authentication via sending a crafted HTTP request to various API endpoints.

Mitigating Controls (NIST 800-53 r5)AI

prevent

AC-3 enforces approved authorizations for access to system resources, directly countering authentication bypass by ensuring only authenticated requests succeed.

prevent

IA-8 requires unique identification and authentication of non-organizational users, preventing remote unauthenticated attackers from exploiting API endpoints.

preventrecover

SI-2 identifies, reports, and corrects flaws like this CVE's authentication bypass through timely patching and remediation per vendor advisories.

Security SummaryAI

CVE-2025-66698 is an authentication bypass vulnerability affecting Semantic Machines version 5.4.8. The flaw, classified under CWE-287 (Improper Authentication), allows attackers to circumvent authentication mechanisms by sending a crafted HTTP request to various API endpoints. It has a CVSS v3.1 base score of 8.6 (AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N), indicating high severity due to its network accessibility, low attack complexity, lack of required privileges or user interaction, expanded scope, and high confidentiality impact.

A remote, unauthenticated attacker can exploit this vulnerability over the network with minimal effort. By crafting and transmitting a malicious HTTP request to targeted API endpoints, the attacker bypasses authentication controls, gaining unauthorized access to potentially sensitive data or functionality. The impact is primarily on confidentiality, enabling the disclosure of high-value information without affecting integrity or availability.

Mitigation details are available in vendor advisories and related resources, including those at http://semantic.com, http://veda.com, and https://github.com/Perunchess/CVE-2025-66698, published on 2026-01-13. Security practitioners should consult these references for patch information, workarounds, or configuration guidance specific to Semantic Machines v5.4.8.

Details

CWE(s)

Affected Products

semantic-machines
veda
5.4.8

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Why these techniques?

CVE-2025-66698 enables remote unauthenticated attackers to bypass authentication on public-facing API endpoints via crafted HTTP requests, directly facilitating T1190: Exploit Public-Facing Application.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

References