CVE-2021-32714CWE-190

Integer Overflow in Chunked Transfer-Encoding

Medium · published July 7, 2021

CVSS v3.1
5.9
EPSS
1%
Percentile
66.8
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
5.9 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.01155 · 66.8th percentile
Weakness
CWE-190 · Integer Overflow or Wraparound
Published
2021-07-07T19:35Z
EPSS history
Timeline
  • 07 JUL 19:35Z
    Integer Overflow in Chunked Transfer-Encoding
    cvelistv5