{"id":"CVE-2026-91920","state":"PUBLISHED","title":"Undertow: undertow: chunkreader message length permits chunk-size overflow","description":"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. 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