CVE-2026-34083

signalk-server: OAuth Authorization Code Theft via Unvalidated Host Header in OIDC Flow

Published Apr 2, 2026 CVSS 3.1 · 6.1 Medium EPSS < 1% KEV · Not listed
Description
Signal K Server is a server application that runs on a central hub in a boat. Prior to version 2.24.0, SignalK Server contains a code-level vulnerability in its OIDC login and logout handlers where the unvalidated HTTP Host header is used to construct the OAuth2 redirect_uri. Because the redirectUri configuration is silently unset by default, an attacker can spoof the Host header to steal OAuth authorization codes and hijack user sessions in realistic deployments as The OIDC provider will then send the authorization code to whatever domain was injected. This issue has been patched in version 2.24.0.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-cxj8-ggf2-p57c Signal K Server: OAuth Authorization Code Theft via Unvalidated Host Header in OIDC Flow
History
Type Values Removed Values Added
First Time appeared Signalk signal K Server
CPEs cpe:2.3:a:signalk:signal_k_server:*:*:*:*:*:*:*:*
Vendors & Products Signalk signal K Server
Type Values Removed Values Added
First Time appeared Signalk
Signalk signalk-server
Vendors & Products Signalk
Signalk signalk-server
Type Values Removed Values Added
Description Signal K Server is a server application that runs on a central hub in a boat. Prior to version 2.24.0, SignalK Server contains a code-level vulnerability in its OIDC login and logout handlers where the unvalidated HTTP Host header is used to construct the OAuth2 redirect_uri. Because the redirectUri configuration is silently unset by default, an attacker can spoof the Host header to steal OAuth authorization codes and hijack user sessions in realistic deployments as The OIDC provider will then send the authorization code to whatever domain was injected. This issue has been patched in version 2.24.0.
Title signalk-server: OAuth Authorization Code Theft via Unvalidated Host Header in OIDC Flow
Weaknesses CWE-346
CWE-601
References
Metrics cvssV3_1

{'score': 6.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Apr 2, 2026, 5:39 PM
Reserved
Mar 25, 2026, 4:21 PM
Status
Analyzed
Published
Apr 2, 2026, 5:16 PM
Modified
Jul 24, 2026, 9:10 PM