CVE-2026-32136

AdGuard Home is a network-wide software for blocking ads and tracking. Prior to 0.107.73, an unauthenticated remote attacker can bypass all authentication in AdGuardHome by sending an HTTP/1.1 request that requests an upgrade to HTTP/2 cleartext (h2c). Once the upgrade is accepted, the resulting HTTP/2 connection is handled by the inner mux, which has no authentication middleware attached. All subsequent HTTP/2 requests on that connection are processed as fully authenticated, regardless of whether any credentials were provided. This vulnerability is fixed in 0.107.73.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/AdguardTeam/AdGuardHome/security/advisories/GHSA-5fg6-wrq4-w5gh	Exploit Vendor Advisory Mitigation

Configurations

Configuration 1 (hide)

cpe:2.3:a:adguard:adguardhome:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-03-11 22:16

Updated : 2026-03-13 20:19

NVD link : CVE-2026-32136

Mitre link : CVE-2026-32136

CVE.ORG link : CVE-2026-32136

JSON object : View

Products Affected

adguard

adguardhome

CWE

CWE-287

Improper Authentication

NVD-CWE-noinfo

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