CVE-2025-57804Medium▾ Sunlith2 allows HTTP Request Smuggling due to illegal characters in headers
▾ Sunlit zone — Low / medium · no exploitation signal
impact 27.5 · likelihood 0.3 · exploitation 0
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Exploit-prediction probability, daily snapshots since Jul 8.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via OSV
1.6%
1.6% → 1.7%
Last analysed / modified upstream
HTTP/2 request splitting vulnerability allows attackers to perform request smuggling attacks by injecting CRLF characters into headers. This occurs when servers downgrade HTTP/2 requests to HTTP/1.1 without properly validating header names/values, enabling attackers to manipulate request boundaries and bypass security controls.
h2 < 4.3.0Upgrade to a patched release:
h2 4.3.0Connected by shared product, vendor, weakness, or advisory.