Integer overflow in Hyper
CVE-2021-32714
hyper is an HTTP library for Rust. In versions prior to 0.14.10, hyper's HTTP server and client code had a flaw that could trigger an integer overflow when decoding chunk sizes that are too big. This allows possible data loss, or if combined with an upstream HTTP proxy that allows chunk sizes larger than hyper does, can result in "request smuggling" or "desync attacks." The vulnerability is patched in version 0.14.10. Two possible workarounds exist. One may reject requests manually that contain a `Transfer-Encoding` header or ensure any upstream proxy rejects `Transfer-Encoding` chunk sizes greater than what fits in 64-bit unsigned integers.
Vulnerability class: Integer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.011 (65.2th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 65th percentile — 65.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.011 · newest: 0.011 · change: 0.000
Affected products
- Hyper
- Hyperium Hyper — versions < 0.14.10
Weakness classification (CWE)
References
- github.com/hyperium/hyper/security/advisories/GHSA-5h46-h7hh-c6x9 (Exploit, Third Party Advisory)
Frequently asked questions
- What is CVE-2021-32714?
- CVE-2021-32714 is a medium-severity vulnerability in Hyper, classified under Integer Overflow or Wraparound. CVSS score: 5.9/10. Published 2021-07-07.
- How severe is CVE-2021-32714?
- Medium severity. CVSS v3 base score is 5.9 out of 10.