openziti zrok up to 2.0.0 ProxyUi Template Engine cross site scripting

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.1$0-$5k3.43-

Summaryinfo

A vulnerability was found in openziti zrok up to 2.0.0 and classified as problematic. This affects an unknown function of the component ProxyUi Template Engine. Such manipulation leads to cross site scripting. This vulnerability is traded as CVE-2026-40302. The attack may be launched remotely. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in openziti zrok up to 2.0.0 and classified as problematic. Affected by this issue is an unknown code of the component ProxyUi Template Engine. The manipulation with an unknown input leads to a cross site scripting vulnerability. Using CWE to declare the problem leads to CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. Impacted is integrity. CVE summarizes:

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.

The advisory is shared for download at github.com. This vulnerability is handled as CVE-2026-40302 since 04/10/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1059.007.

Upgrading to version 2.0.1 eliminates this vulnerability. The upgrade is hosted for download at github.com.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.2
VulDB Meta Temp Score: 5.1

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.1
CNA Vector (GitHub_M): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Cross site scripting
CWE: CWE-79 / CWE-94 / CWE-74
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: zrok 2.0.1

Timelineinfo

04/10/2026 CVE reserved
04/17/2026 +7 days Advisory disclosed
04/17/2026 +0 days VulDB entry created
04/17/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-4fxq-2x3x-6xqx
Status: Confirmed

CVE: CVE-2026-40302 (🔒)
GCVE (CVE): GCVE-0-2026-40302
GCVE (VulDB): GCVE-100-358124

Entryinfo

Created: 04/17/2026 23:48
Changes: 04/17/2026 23:48 (66)
Complete: 🔍
Cache ID: 216::103

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