CVE-2026-66753: medium-severity vulnerability in tiny-http
tiny-http 0.12.0 HTTP Response Splitting via Header Injection
Published · Updated
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33Vexday Risk Score
No sign of exploitation. It has a public proof of concept.
ssvc Attendcvss 6.3epss 0.3%
from disclosure to weaponsame day
Published on NVDJul 28
1st PoCJul 26
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:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
Affected products
tiny-http · tiny-httppublic PoCs found — 2
githubgithub.com/theopaid/CVE-2026-66753-HTTP-Header-Injection-via-Unvalidated-CR-and-LF-in-Header-Values-tiny_http-★ 0cve_referencegithub.com/theopaid/HTTP-Header-Injection-via-Unvalidated-CR-and-LF-in-Header-Values-tiny_http-/tree/masterunverified⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
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