CVE-2021-38512

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.8% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2021-08-10 · updated 2026-06-17
Weakness: CWE-444

Description

An issue was discovered in the actix-http crate before 3.0.0-beta.9 for Rust. HTTP/1 request smuggling (aka HRS) can occur, potentially leading to credential disclosure.

Affected products

Actix-Http: before 3.0.0; 3.0.0, 3.0.0-beta1, 3.0.0-beta2, 3.0.0-beta3, 3.0.0-beta4, 3.0.0-beta5 (+3) — fixed in 3.0.0
Fedoraproject Fedora: 34

How to fix

Upgrade to a fixed version: Actix-Http 3.0.0. Check the vendor advisory for mitigations.

References

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/67URRW4K47SR6LNQB4YALPLGGQMQK7HO/
https://raw.githubusercontent.com/rustsec/advisory-db/main/crates/actix-http/RUSTSEC-2021-0081.md
https://rustsec.org/advisories/RUSTSEC-2021-0081.html
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/67URRW4K47SR6LNQB4YALPLGGQMQK7HO/
https://raw.githubusercontent.com/rustsec/advisory-db/main/crates/actix-http/RUSTSEC-2021-0081.md
https://rustsec.org/advisories/RUSTSEC-2021-0081.html

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