CVE-2026-101059

utcp-http before 1.1.4 OAuth2 tokenUrl Trust Boundary Bypass

Published Sep 27, 2026 CVSS 4.0 · 7.1 High EPSS < 1% KEV · Not listed
Description
utcp-http before 1.1.4 fails to validate the OAuth2 tokenUrl field from remote OpenAPI specifications, allowing attackers to redirect credential submission to arbitrary endpoints. When a victim registers an attacker-controlled OpenAPI spec and invokes a generated OAuth2-protected tool, the library POSTs the victim's client_id and client_secret to the attacker-supplied token endpoint without URL validation.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Universal-tool-calling-protocol
Universal-tool-calling-protocol python-utcp
Vendors & Products Universal-tool-calling-protocol
Universal-tool-calling-protocol python-utcp
Type Values Removed Values Added
Description utcp-http before 1.1.4 fails to validate the OAuth2 tokenUrl field from remote OpenAPI specifications, allowing attackers to redirect credential submission to arbitrary endpoints. When a victim registers an attacker-controlled OpenAPI spec and invokes a generated OAuth2-protected tool, the library POSTs the victim's client_id and client_secret to the attacker-supplied token endpoint without URL validation.
Title utcp-http before 1.1.4 OAuth2 tokenUrl Trust Boundary Bypass
Weaknesses CWE-918
References
Metrics cvssV3_1

{'score': 7.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N'}

cvssV4_0

{'score': 7.1, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
VulnCheck
Published
Updated
Sep 28, 2026, 2:02 PM
Reserved
Sep 27, 2026, 4:38 PM
Status
Deferred
Published
Sep 27, 2026, 6:16 PM
Modified
Sep 30, 2026, 5:32 PM