| Name | CVE-2026-54387 |
| Description | 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. |
| Source | CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
| Debian Bugs | 1140350 |
Vulnerable and fixed packages
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|
| tinyproxy (PTS) | bullseye | 1.10.0-5 | vulnerable |
| bullseye (security) | 1.10.0-5+deb11u1 | vulnerable |
| bookworm, bookworm (security) | 1.11.1-2.1+deb12u1 | vulnerable |
| trixie | 1.11.2-1 | vulnerable |
| forky, sid | 1.11.3-1 | vulnerable |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|
| tinyproxy | source | (unstable) | (unfixed) | | | 1140350 |
Notes
[trixie] - tinyproxy <no-dsa> (Minor issue)
[bookworm] - tinyproxy <postponed> (Minor issue; forward proxy does not pool backend connections across clients, exploitation needs a shared upstream proxy/cache, no upstream release with the fix)
[bullseye] - tinyproxy <postponed> (Minor issue; forward proxy does not pool backend connections across clients, exploitation needs a shared upstream proxy/cache, no upstream release with the fix)
https://github.com/tinyproxy/tinyproxy/issues/609
https://github.com/tinyproxy/tinyproxy/pull/610
Fixed by: https://github.com/tinyproxy/tinyproxy/commit/623bfc093df009296f0b85d40bc677ef9d5c09bb