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    "cveMetadata": {
        "cveId": "CVE-2026-31842",
        "assignerOrgId": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c",
        "state": "PUBLISHED",
        "assignerShortName": "TuranSec",
        "dateReserved": "2026-03-09T18:20:23.398Z",
        "datePublished": "2026-04-07T11:17:33.621Z",
        "dateUpdated": "2026-08-10T11:43:29.288Z"
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                "shortName": "TuranSec",
                "dateUpdated": "2026-08-10T11:43:29.288Z"
            },
            "title": "Tinyproxy HTTP request parsing desynchronization via case-sensitive Transfer-Encoding handling",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "cweId": "CWE-444",
                            "description": "CWE-444 Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "impacts": [
                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "value": "An unauthenticated remote attacker can trigger HTTP request parsing desynchronization using a mixed-case Transfer-Encoding header (e.g., 'Chunked'), leading to backend connection hangs and denial of service. In certain deployments, request-body inspection and filtering mechanisms relying on Tinyproxy may also be bypassed."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "vendor": "Tinyproxy Project",
                    "product": "Tinyproxy",
                    "platforms": [
                        "all"
                    ],
                    "collectionURL": "https://github.com/tinyproxy/tinyproxy",
                    "versions": [
                        {
                            "status": "affected",
                            "version": "0",
                            "lessThanOrEqual": "1.11.3",
                            "versionType": "custom"
                        }
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            ],
            "descriptions": [
                {
                    "lang": "en",
                    "value": "Tinyproxy through 1.11.3 is vulnerable to HTTP request parsing desynchronization due to a case-sensitive comparison of the Transfer-Encoding header in src/reqs.c. The is_chunked_transfer function uses strcmp to compare the header value against \"chunked\", even though RFC 7230 specifies that transfer-coding names are case-insensitive.",
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                            "base64": false,
                            "value": "<p>Tinyproxy through 1.11.3 is vulnerable to HTTP request parsing desynchronization due to a case-sensitive comparison of the Transfer-Encoding header in src/reqs.c. The is_chunked_transfer function uses strcmp to compare the header value against \"chunked\", even though RFC 7230 specifies that transfer-coding names are case-insensitive.</p>"
                        }
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                }
            ],
            "references": [
                {
                    "url": "https://github.com/tinyproxy/tinyproxy/issues/604",
                    "name": "Upstream issue report and reproduction details",
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                        "technical-description",
                        "third-party-advisory"
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                },
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                    "url": "https://github.com/tinyproxy/tinyproxy",
                    "name": "Tinyproxy upstream project",
                    "tags": [
                        "product"
                    ]
                },
                {
                    "url": "https://datatracker.ietf.org/doc/html/rfc7230",
                    "name": "RFC 7230: transfer-coding names are case-insensitive",
                    "tags": [
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                        "attackVector": "NETWORK",
                        "attackComplexity": "LOW",
                        "attackRequirements": "NONE",
                        "privilegesRequired": "NONE",
                        "userInteraction": "NONE",
                        "vulnConfidentialityImpact": "NONE",
                        "subConfidentialityImpact": "NONE",
                        "vulnIntegrityImpact": "NONE",
                        "subIntegrityImpact": "NONE",
                        "vulnAvailabilityImpact": "HIGH",
                        "subAvailabilityImpact": "NONE",
                        "exploitMaturity": "NOT_DEFINED",
                        "Safety": "NOT_DEFINED",
                        "Automatable": "NOT_DEFINED",
                        "Recovery": "NOT_DEFINED",
                        "valueDensity": "NOT_DEFINED",
                        "vulnerabilityResponseEffort": "NOT_DEFINED",
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                        "accessVector": "NETWORK",
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                        "integrityImpact": "NONE",
                        "availabilityImpact": "COMPLETE",
                        "baseScore": 7.8,
                        "vectorString": "AV:N/AC:L/Au:N/C:N/I:N/A:C"
                    }
                }
            ],
            "credits": [
                {
                    "lang": "en",
                    "value": "Muxammadiyev G'iyosiddin",
                    "type": "finder"
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            "source": {
                "discovery": "EXTERNAL"
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            "datePublic": "2026-04-07T11:17:33.621Z"
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        "adp": [
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                "metrics": [
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                                "timestamp": "2026-04-07T16:30:26.482367Z",
                                "id": "CVE-2026-31842",
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                                "version": "2.0.3"
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                "title": "CISA ADP Vulnrichment",
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