CVE-2021-21299
Summary
| CVE | CVE-2021-21299 |
|---|---|
| State | PUBLIC |
| Assigner | [email protected] |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2021-02-11 18:15:00 UTC |
| Updated | 2021-02-19 18:28:00 UTC |
| Description | hyper is an open-source HTTP library for Rust (crates.io). In hyper from version 0.12.0 and before versions 0.13.10 and 0.14.3 there is a vulnerability that can enable a request smuggling attack. The HTTP server code had a flaw that incorrectly understands some requests with multiple transfer-encoding headers to have a chunked payload, when it should have been rejected as illegal. This combined with an upstream HTTP proxy that understands the request payload boundary differently can result in "request smuggling" or "desync attacks". To determine if vulnerable, all these things must be true: 1) Using hyper as an HTTP server (the client is not affected), 2) Using HTTP/1.1 (HTTP/2 does not use transfer-encoding), 3) Using a vulnerable HTTP proxy upstream to hyper. If an upstream proxy correctly rejects the illegal transfer-encoding headers, the desync attack cannot succeed. If there is no proxy upstream of hyper, hyper cannot start the desync attack, as the client will repair the headers before forwarding. This is fixed in versions 0.14.3 and 0.13.10. As a workaround one can take the following options: 1) Reject requests that contain a `transfer-encoding` header, 2) Ensure any upstream proxy handles `transfer-encoding` correctly. |
Risk And Classification
Problem Types: CWE-444
NVD Known Affected Configurations (CPE 2.3)
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| Cargo | MISC | crates.io | Product, Third Party Advisory |
| Multiple Transfer-Encoding headers misinterprets request payload · Advisory · hyperium/hyper · GitHub | CONFIRM | github.com | Third Party Advisory |
| About RustSec › RustSec Advisory Database | MISC | rustsec.org | Third Party Advisory |
| fix(http1): fix server misinterpretting multiple Transfer-Encoding he… · hyperium/hyper@8f93123 · GitHub | MISC | github.com | Patch, Third Party Advisory |
| HTTP Desync Attacks: Request Smuggling Reborn | PortSwigger Research | MISC | portswigger.net | Third Party Advisory |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
Legacy QID Mappings
- 184396 Debian Security Update for rust-hyper (CVE-2021-21299)