CVE-2026-40302

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{"affected": [{"affectedData": [{"product": "zrok", "vendor": "openziti", "versions": [{"status": "affected", "version": "< 2.0.1"}]}], "source": "security-advisories@github.com"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:netfoundry:zrok:*:*:*:*:*:*:*:*", "matchCriteriaId": "70C6F018-6D34-4A75-A49D-A795B0A5B056", "versionEndExcluding": "2.0.1", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "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."}, {"lang": "es", "value": "zrok es un software para compartir servicios web, archivos y recursos de red. Antes de la versi\u00f3n 2.0.1, el motor de plantillas proxyUi utiliza text/template de Go (que no realiza escape de HTML) en lugar de html/template. Los manejadores de callback de GitHub OAuth tanto en publicProxy como en dynamicProxy incrustan el par\u00e1metro de consulta refreshInterval controlado por el atacante textualmente en un mensaje de error cuando time.ParseDuration falla, y renderizan ese error sin escape en HTML. Un atacante puede entregar una URL de inicio de sesi\u00f3n manipulada a una v\u00edctima; despu\u00e9s de que la v\u00edctima completa el flujo de GitHub OAuth, la p\u00e1gina de callback ejecuta JavaScript arbitrario en el origen del servidor OAuth. La versi\u00f3n 2.0.1 corrige el problema."}], "id": "CVE-2026-40302", "lastModified": "2026-10-26T22:10:00.163", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 6.1, "baseSeverity": "MEDIUM", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "CHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 2.8, "impactScore": 2.7, "source": "security-advisories@github.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-40302", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-04-18T03:07:00.447331Z", "version": "2.0.3"}}]}, "published": "2026-04-17T21:16:34.997", "references": [{"source": "security-advisories@github.com", "tags": ["Release Notes"], "url": "https://github.com/openziti/zrok/releases/tag/v2.0.1"}, {"source": "security-advisories@github.com", "tags": ["Vendor Advisory"], "url": "https://github.com/openziti/zrok/security/advisories/GHSA-4fxq-2x3x-6xqx"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-79"}, {"lang": "en", "value": "CWE-116"}], "source": "security-advisories@github.com", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,2.0.1)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "cna", "scores": [{"score": 100.0, "source": "cna"}]}, "original": {"product": "zrok", "source": "cna", "vendor": "openziti"}, "product": "zrok", "vendor": "openziti"}], "analysis": {"en": {"generated_at": "2026-04-18T08:57:29.879433+00:00", "value": {"mitigation_remediation": ["Upgrade to openziti zrok v2.0.1 or later.", "If an upgrade cannot be performed immediately, block or escape any refreshInterval query parameter in the callback URL to prevent unescaped rendering.", "Replace the use of text/template with a safe alternative such as html/template for all user\u2011supplied content to ensure proper HTML escaping."], "summary": {"action": "Immediate Patch", "impact": "Reflected XSS in OAuth callback"}, "threat_synthesis": {"affected_systems": "The issue affects any openziti zrok deployment running a release earlier than v2.0.1. Users of those versions should verify their installed version and plan an update to the patched release.", "description_and_impact": "zrok is a tool for sharing services that, before version 2.0.1, uses Go\u2019s text/template in its proxyUi engine, which performs no HTML escaping. The GitHub OAuth callback handlers in both publicProxy and dynamicProxy embed the attacker\u2011controlled refreshInterval query parameter directly into an error message when time.ParseDuration fails. That error is rendered without escaping, allowing arbitrary JavaScript to execute in the OAuth server\u2019s origin. This flaw, grounded in CWE\u201179 (Cross\u2011Site Scripting) and CWE\u2011116 (Improper Encoding), lets an adversary inject code whenever a victim follows a malicious login link and completes the OAuth flow.", "risk_and_exploitability": "The vulnerability carries a CVSS score of 6.1, indicating moderate severity, and currently has no EPSS score available. It is not listed in CISA\u2019s KEV catalog. The likely attack vector requires a victim to click a crafted OAuth URL; after authentication, the callback page executes the injected script in the context of the OAuth provider\u2019s origin, enabling client\u2011side compromise of the user\u2019s session."}}}}, "created": "2026-04-18T09:00:05.902117+00:00", "updated": "2026-04-20T14:59:34.832745+00:00", "vendors": ["openziti", "openziti$PRODUCT$zrok"]}