All vulnerabilities
CVE-2026-101059GHSA-8cp3-qxj6-px34

python-utcp: utcp-http before 1.1.4 OAuth2 tokenUrl Trust Boundary Bypass

universal-tool-calling-protocol python-utcpPyPIRuntimes & languages
Open in ThreatlineRecord JSON
CVSS
7.1High
ExploitationPublic exploit codeCISA's assessment says proof of concept code is public, assessed 28 Sep 2026. Not in the KEV catalogCISA via CVE List
Exploit odds (EPSS)0.18%Chance of exploitation activity in the next 30 days, higher than 7% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in1.1.4Fixed versionCVE List
Published27 Sep 2026Updated 28 Sep 2026CVE List

What fixes it

  • 1.1.4python-utcpCVE List
  • 1.1.4utcp-http, PyPIOSVpip install "utcp-http>=1.1.4"

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

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.

Text from CVE List

Affected versions 13

  • python-utcpaffected: all versions before 1.1.4CVE List
  • python-utcpunaffected: 1.1.4CVE List
  • utcp-http, PyPIfrom first release, fixed in 1.1.4OSV
  • utcp-http, PyPI1.0.0OSV
  • utcp-http, PyPI1.0.1OSV
  • utcp-http, PyPI1.0.2OSV
  • utcp-http, PyPI1.0.3OSV
  • utcp-http, PyPI1.0.4OSV
  • utcp-http, PyPI1.0.5OSV
  • utcp-http, PyPI1.1.0OSV
  • utcp-http, PyPI1.1.1OSV
  • utcp-http, PyPI1.1.2OSV
  • utcp-http, PyPI1.1.3OSV

References 2