CVE-2026-66753

tiny-http through 0.12.0 contains an HTTP header injection vulnerability that allows attackers to inject carriage return (0x0D) and line feed (0x0A) bytes into HTTP header values on both request and response sides due to insufficient validation in header parsing and serialization. Attackers can exploit this injection primitive to perform response splitting, cache poisoning, session fixation via Set-Cookie injection, security header override, and request smuggling against line-feed-tolerant backends.

CVSS v3 3.7 LOW

3.7^/10

CVSS v3 : LOW

Vector :

Exploitability : 2.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/theopaid/HTTP-Header-Injection-via-Unvalidated-CR-and-LF-in-Header-Values-tiny_http-/tree/master
https://www.vulncheck.com/advisories/tiny-http-http-response-splitting-via-header-injection

Configurations

No configuration.

History

28 Jul 2026, 17:17

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~5.3~~	v2 : unknown v3 : 3.7

28 Jul 2026, 16:20

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-28 16:20

Updated : 2026-07-30 20:03

NVD link : CVE-2026-66753

Mitre link : CVE-2026-66753

CVE.ORG link : CVE-2026-66753

JSON object : View

Products Affected

No product.

CWE

CWE-113

Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting')

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