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        "state": "PUBLISHED",
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        "dateReserved": "2026-09-15T10:20:33.140Z",
        "datePublished": "2026-10-30T01:16:53.416Z",
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            "title": "Undertow: undertow: chunkreader message length permits chunk-size overflow",
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                        "attackVector": "NETWORK",
                        "availabilityImpact": "LOW",
                        "baseScore": 6.5,
                        "baseSeverity": "MEDIUM",
                        "confidentialityImpact": "NONE",
                        "integrityImpact": "LOW",
                        "privilegesRequired": "NONE",
                        "scope": "UNCHANGED",
                        "userInteraction": "NONE",
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                        "version": "3.1"
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                    "lang": "en",
                    "value": "A flaw was found in the ChunkReader component of the Undertow web server, which is used to handle chunked transfer encoding in HTTP requests. The issue occurs because a security check for the chunk size is performed before the value is shifted, allowing a specifically crafted 15-digit chunk size to bypass the limit and overflow into internal state flags. This can cause the server to terminate a request body prematurely and interpret the remaining data as a separate, smuggled request."
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            "datePublic": "2026-10-29T12:11:57.588Z",
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                            "cweId": "CWE-444",
                            "description": "Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')",
                            "lang": "en",
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            "timeline": [
                {
                    "lang": "en",
                    "time": "2026-09-04T17:07:17.250Z",
                    "value": "Reported to Red Hat."
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                    "time": "2026-10-29T12:11:57.588Z",
                    "value": "Made public."
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                {
                    "lang": "en",
                    "value": "Red Hat would like to thank Arpit Jain for reporting this issue."
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