title: HTTP Response Splitting
description: Uvicorn before 0.11.7 is vulnerable to HTTP response splitting. CRLF sequences are not escaped in the value of HTTP headers. Attackers can exploit this to add arbitrary headers to HTTP responses, or even return an arbitrary response body, whenever crafted input is used to construct HTTP headers.
problem types: HTTP Response Splitting
affected:
{
product: uvicorn
vendor: n/a
versions:
lessThan: unspecified, status: affected, version: 0, versionType: custom
}
metrics:
cvssV3_1: [
attackComplexity: LOW
attackVector: NETWORK
availabilityImpact: NONE
baseScore: 5.3
baseSeverity: MEDIUM
confidentialityImpact: NONE
exploitCodeMaturity: PROOF_OF_CONCEPT
integrityImpact: LOW
privilegesRequired: NONE
remediationLevel: UNAVAILABLE
reportConfidence: CONFIRMED
scope: UNCHANGED
temporalScore: 5
temporalSeverity: MEDIUM
userInteraction: NONE
vectorString: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N/E:P/RL:U/RC:C
version: 3.1
]