CVE-2025-13427Network attack vector

Unauthenticated agent access via manipulated initialization parameters

Published Dec 18, 2025 · Updated Dec 18, 2025

Authentication bypass in Google Dialogflow CX Messenger through August 20, 2025 allows remote attackers to access restricted agents. The integration accepted manipulated initialization parameters or crafted API requests without enforcing the configured third-party identity check. The flaw required an agent using an authenticated API with a third-party identity and exposed agent knowledge while permitting unauthorized intent triggering.

CVSS severity6.9
Medium
EPSS probability0.47%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authentication bypass in Google Dialogflow CX Messenger through August 20, 2025 allows remote attackers to access restricted agents. The integration accepted manipulated initialization parameters or crafted API requests without enforcing the configured third-party identity check. The flaw required an agent using an authenticated API with a third-party identity and exposed agent knowledge while permitting unauthorized intent triggering.

The record

CVE
CVE-2025-13427
Published
Dec 18, 2025
Updated
Dec 18, 2025
Vendor
Go standard library
Product
Dialogflow CX Messenger
Classifications
CWE-287, CAPEC-115, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 18, 2025CVE publishedPublication date reported by the CVE source.
  2. Dec 18, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <=2025-08-20

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Go standard library · Dialogflow CX Messengerversion=0 <=2025-08-20

Published CVSS scores

6.9GoogleCloudCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-287Improper Authentication
CAPEC-115Authentication Bypass
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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