CVE-2026-66753
tiny-http 0.12.0 HTTP Response Splitting via Header Injection
MEDIUM 6.3EPSS 0.3%
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.
- Affected
- tiny-http
- CVSS v4.0 VULNCHECK
- 6.3 MEDIUM
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS v3.1 VULNCHECK
- 3.7 LOW
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N - EPSS
- 0.30% chance of exploitation in the next 30 days, 21st percentile
- Published
- 2026-07-28
- Updated
- 2026-08-14
Proof-of-concept exploits (1)
- theopaid/HTTP-Header-Injection-via-Unvalidated-CR-and-LF-in-Header-Values-tiny_http-/tree…0★ · 2026-07-28