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    "cveMetadata": {
        "cveId": "CVE-2026-76835",
        "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "state": "PUBLISHED",
        "assignerShortName": "VulnCheck",
        "dateReserved": "2026-08-19T20:34:00.154Z",
        "datePublished": "2026-08-24T17:55:39.829Z",
        "dateUpdated": "2026-10-08T15:25:05.218Z"
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                "dateUpdated": "2026-10-08T15:25:05.218Z"
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            "datePublic": "2026-08-17T00:00:00.000Z",
            "title": "OAuth2 Proxy 7.15.2 through 7.15.4 Authentication Bypass via X-Forwarded-Uri Under the Default Trusted Proxy Set",
            "descriptions": [
                {
                    "lang": "en",
                    "value": "OAuth2 Proxy honours a client-supplied X-Forwarded-Uri header when deciding whether a request may skip authentication, because the guard added for CVE-2026-40575 is inert in the default reverse-proxy configuration. GetRequestURI in pkg/requests/util/util.go prefers that header over the real request URI whenever CanTrustForwardedHeaders returns true, and isAllowedPath in oauthproxy.go matches the skip_auth_routes and skip_auth_regex allow list against the resulting path. CanTrustForwardedHeaders in pkg/apis/middleware/scope.go grants that trust when the caller's address is in the trusted proxy set, and buildTrustedProxyNetSet falls back to defaultTrustedProxyIPs, which is 0.0.0.0/0 and ::/0, whenever reverse proxy mode is enabled without trusted_proxy_ip configured. Every client is therefore treated as a trusted proxy. An unauthenticated attacker can request a protected upstream path while setting X-Forwarded-Uri to a value matching an allow-listed route, so the skip-auth decision is made against the spoofed value while the upstream receives the protected path unchanged."
                }
            ],
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                {
                    "descriptions": [
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                            "lang": "en",
                            "cweId": "CWE-290",
                            "description": "Authentication Bypass by Spoofing",
                            "type": "CWE"
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                    "product": "oauth2-proxy",
                    "defaultStatus": "unaffected",
                    "versions": [
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                            "version": "7.15.2",
                            "lessThanOrEqual": "7.15.4",
                            "status": "affected",
                            "versionType": "semver"
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                    ],
                    "repo": "https://github.com/oauth2-proxy/oauth2-proxy",
                    "packageURL": "pkg:golang/github.com/oauth2-proxy/oauth2-proxy/v7"
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                                    "versionEndIncluding": "7.15.4"
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                        "attackVector": "NETWORK",
                        "attackComplexity": "LOW",
                        "attackRequirements": "NONE",
                        "privilegesRequired": "NONE",
                        "userInteraction": "NONE",
                        "vulnConfidentialityImpact": "HIGH",
                        "vulnIntegrityImpact": "HIGH",
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                    "url": "https://github.com/oauth2-proxy/oauth2-proxy/security/advisories/GHSA-7x63-xv5r-3p2x",
                    "name": "GitHub Security Advisory (GHSA-7x63-xv5r-3p2x)",
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                    "name": "VulnCheck Advisory: OAuth2 Proxy 7.15.2 through 7.15.4 Authentication Bypass via X-Forwarded-Uri Under the Default Trusted Proxy Set",
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                    "url": "https://www.vulncheck.com/advisories/oauth2-proxy-through-authentication-bypass-via-x-forwarded-uri-under-the-default-trusted-proxy-set"
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            "credits": [
                {
                    "lang": "en",
                    "value": "George Chen",
                    "type": "finder"
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                "metrics": [
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                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-08-24T20:00:05.680574Z",
                                "id": "CVE-2026-76835",
                                "options": [
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                                "role": "CISA Coordinator",
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