VULNERABILITY INTELLIGENCE
CVE-2026-54388
CVSS score9.3 CRITICAL
EPSS probability0.44%
CISA KEVNot currently listed
Published2026-06-17
Last modified2026-07-14
CVSS vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
Description
Tinyproxy through 1.11.3, fixed in commit 364cdb6, fails to reject requests containing multiple Content-Length headers with differing values, forwarding all duplicate headers to the backend while using the first value to determine how many request body bytes to consume. Remote attackers can desynchronize the proxy and backend parser state, allowing injection of arbitrary HTTP requests to the backend to enable cache poisoning, access control bypass, and request hijacking.
Weakness classification
- CWE-444: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')