CVE-2026-58055
Published: July 1, 2026Last modified: August 11, 2026
Description
nghttp2's nghttpx proxy through 1.69.0 forwards an HTTP/1.1 Upgrade request that also carries a Content-Length header and body onto reusable keep-alive backend connections, re-adding the Upgrade and Connection headers while passing Content-Length verbatim. A backend that resolves the resulting ambiguous message in the attacker's favor enables HTTP request/response smuggling and cross-client response-queue poisoning.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 5.4 |
| Attack Vector | NETWORK |
| Attack complexity | HIGH |
| Privileges required | NONE |
| User interaction | NONE |
| Scope | CHANGED |
| Confidentiality | LOW |
| Integrity impact | LOW |
| Availability impact | NONE |
| Vector | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | nghttp2 | Unknown (1.51.0-r0) |
| 25 LTS | nghttp2 | Fixed (1.69.0-r1) | |
| Stream | nghttp2 | Fixed (1.70.0-r0) | |
| Hardened Containers | 23 LTS | nghttp2 | Unknown (1.51.0-r0) |
| 25 LTS | nghttp2 | Fixed (1.69.0-r1) | |
| Stream | nghttp2 | Fixed (1.70.0-r0) |