SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2021-32714

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.

CRITICAL 9.1EPSS 1.13%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.13%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

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.

CVSS 3.1
9.1 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
EPSS
1.13% probability · 65th percentile
CISA KEV
Not listed
Weakness
CWE-190
Affected
hyper/hyper
Source
security-advisories@github.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.