CVE-2026-101090

Nezha 2.2.3 contains a Host header injection regression in the OAuth2 redirect endpoint. When the new optional dashboard_host setting is empty, /api/v1/oauth2/{provider} (cmd/dashboard/controller/oauth2.go) reflects the attacker-supplied HTTP Host header into the redirect_uri sent to the identity provider instead of falling back to the configured install_host. An attacker who induces a victim to begin OAuth2 login via a request that reaches Nezha with a forged Host header can cause an attacker-controlled callback URL to be used as the redirect_uri; if the OAuth2 provider accepts it, the victim's authorization code is delivered to the attacker origin, allowing the attacker to complete the OAuth2 login/binding flow and take over the account. This regresses the fix for GHSA-9rc6-8cjv-rcvx and is configuration-dependent (dashboard_host empty). At the time of the advisory no patched version was available.

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/nezhahq/nezha/security/advisories/GHSA-rf68-8gjr-36q7
https://www.vulncheck.com/advisories/nezha-through-2.2.3-host-header-injection-via-oauth2-redirect-uri
https://github.com/nezhahq/nezha/security/advisories/GHSA-rf68-8gjr-36q7

Configurations

No configuration.

History

28 Sep 2026, 13:17

Type	Values Removed	Values Added
References	~~() https://github.com/nezhahq/nezha/security/advisories/GHSA-rf68-8gjr-36q7 -~~	() https://github.com/nezhahq/nezha/security/advisories/GHSA-rf68-8gjr-36q7 -

27 Sep 2026, 21:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-27 21:17

Updated : 2026-09-28 21:02

NVD link : CVE-2026-101090

Mitre link : CVE-2026-101090

CVE.ORG link : CVE-2026-101090

JSON object : View

Products Affected

No product.

CWE

CWE-601

URL Redirection to Untrusted Site ('Open Redirect')

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