CVE-2026-54387
Tinyproxy through 1.11.3, fixed in commit ff45d3b, fails to reconcile conflicting Content-Length and Transfer-Encoding: chunked headers, forwarding both verbatim to the backend while using Content-Length 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.
Published:Jun 17, 2026
Last Modified:Jul 14, 2026
EPS:Jun 17, 2026
EPSS Score:0.00439
CVSS Score:9.1
Affected Products
Vendor
Product
Action
Vendor
Tinyproxy
Product
Tinyproxy
Tinyproxy
Tinyproxy
Vendor
Tinyproxy Project
Product
Tinyproxy
Tinyproxy Project
Tinyproxy
Exploits
No exploit reference
Common Weakness Enumeration
Common Attack Pattern Enumeration and Classification (CAPEC)
Related CVEs
Common Vulnerability Scoring System
Attack Vector
Network
Adjacent
Local
Physical
Privileges Required
None
Low
High
User Interaction
None
Required
Scope
Unchanged
Changed
Confidentiality
None
Low
High
Integrity
None
Low
High
Availability
None
Low
High
