CVE-2021-32714

Public Exploit
Integer Overflow in Chunked Transfer-Encoding

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.

Category

5.9
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.40%
Third-Party Advisory github.com
Affected: hyperium hyper
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-32714?
CVE-2021-32714 has been scored as a medium severity vulnerability.
How to fix CVE-2021-32714?
To fix CVE-2021-32714, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-32714 being actively exploited in the wild?
It is possible that CVE-2021-32714 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-32714?
CVE-2021-32714 affects hyperium hyper.
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