CVE-2026-40302 (GCVE-0-2026-40302)
Vulnerability from cvelistv5 – Published: 2026-04-17 20:56 – Updated: 2026-04-18 03:07
VLAI
EPSS
VEX
Title
zrok has reflected XSS in GitHub OAuth callback via unsanitized refreshInterval error rendering
Summary
zrok is software for sharing web services, files, and network resources. Prior to version 2.0.1, the proxyUi template engine uses Go's text/template (which performs no HTML escaping) instead of html/template. The GitHub OAuth callback handlers in both publicProxy and dynamicProxy embed the attacker-controlled refreshInterval query parameter verbatim into an error message when time.ParseDuration fails, and render that error unescaped into HTML. An attacker can deliver a crafted login URL to a victim; after the victim completes the GitHub OAuth flow, the callback page executes arbitrary JavaScript in the OAuth server's origin. Version 2.0.1 patches the issue.
Severity
6.1 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-18 03:07 UTC
CWE
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/openziti/zrok/security/advisor… | x_refsource_CONFIRM |
| https://github.com/openziti/zrok/releases/tag/v2.0.1 | x_refsource_MISC |
Impacted products
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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