CVE-2026-75871

Analyzed Analyzed - Analysis Complete

Authentication Bypass in GitLab AI Gateway

Publication date: 2026-08-27

Last updated on: 2026-09-01

Assigner: GitLab Inc.

Description

GitLab has remediated a vulnerability in the GitLab AI Gateway component affecting all versions of the AI Gateway from 18.10 to 19.0.12, 19.1 to 19.1.7, and 19.2 to 19.2.2 that could have allowed an authenticated user with Duo Agent Platform access to redirect outbound model requests to an externally-controlled endpoint via a crafted inline flow configuration that overrides the HTTP Host header, resulting in disclosure of Google Cloud Vertex cloud service credentials and private signing keys.

CVSS Scores

EPSS Scores

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Meta Information

Published

2026-08-27

Last Modified

2026-09-01

Generated

2026-09-17

AI Q&A

2026-08-27

EPSS Evaluated

2026-09-15

NVD

CVE-2026-75871

EUVD

EUVD-2026-67088

Affected Vendors & Products

Vendor	Product	Version / Range
gitlab	gitlab	From 18.10.0 (inc) to 19.0.12 (exc)
gitlab	gitlab	From 19.1.0 (inc) to 19.1.7 (exc)
gitlab	gitlab	From 19.2.0 (inc) to 19.2.2 (exc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-918	The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.

Attack-Flow Graph

Executive Summary

This vulnerability in GitLab's AI Gateway allows an authenticated user with Duo Agent Platform access to redirect outbound AI model requests to a malicious endpoint by manipulating the HTTP Host header. This could lead to exposure of Google Cloud Vertex service credentials and private signing keys.

Detection Guidance

This vulnerability affects GitLab AI Gateway versions 18.10 to 19.0.12, 19.1 to 19.1.7, and 19.2 to 19.2.2. To detect it, check the installed version of GitLab AI Gateway using commands like 'gitlab-ai-gateway --version' or inspect the package manager logs. Review configuration files for suspicious inline flow settings that override HTTP Host headers.

Impact Analysis

If exploited, this vulnerability could result in unauthorized access to sensitive cloud service credentials and private keys, potentially leading to data breaches, service disruption, or further attacks on connected systems.

Compliance Impact

This vulnerability could lead to unauthorized access to sensitive data, violating confidentiality requirements in GDPR and HIPAA. Organizations may face compliance violations, legal penalties, and reputational damage if exploited.

Mitigation Strategies

Upgrade GitLab AI Gateway to a patched version (19.0.12, 19.1.7, or 19.2.2 or later) to address the vulnerability in the affected versions.

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