Vulnerability in Hyper
CVE-2021-32715
hyper is an HTTP library for rust. hyper's HTTP/1 server code had a flaw that incorrectly parses and accepts requests with a `Content-Length` header with a prefixed plus sign, when it should have been rejected as illegal. This combined with an upstream HTTP proxy that doesn't parse such `Content-Length` headers, but forwards them, can result in "request smuggling" or "desync attacks". The flaw exists in all prior versions of hyper prior to 0.14.10, if built with `rustc` v1.5.0 or newer. The vulnerability is patched in hyper version 0.14.10. Two workarounds exist: One may reject requests manually that contain a plus sign prefix in the `Content-Length` header or ensure any upstream proxy handles `Content-Length` headers with a plus sign prefix.
Vulnerability class: HTTP Request Smuggling
EPSS: 0.009 (55.6th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 3.1 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N.
Affected products
- Hyper
- Hyperium Hyper — versions < 0.14.10
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Exploit, Third Party Advisory)
- security-advisories@github.com (Patch, Third Party Advisory, x_refsource_MISC)
Frequently asked questions
- What is CVE-2021-32715?
- CVE-2021-32715 is a low-severity vulnerability in Hyper, classified under Inconsistent Interpretation of HTTP Requests (HTTP Request/Response Smuggling). CVSS score: 3.1/10. Published 2021-07-07.
- How severe is CVE-2021-32715?
- Low severity. CVSS v3 base score is 3.1 out of 10.