CVE-2026-5222

Cargo between 1.68 and 1.96 incorrectly normalized the URLs of third-party registries using the sparse index protocol. If a hosting provider allowed multiple registries to be hosted with arbitrary names within the same domain, an attacker able to publish crates in a registry could obtain the credentials of others users of the same registry. The severity of the vulnerability is **low**, due to the extremely niche requirements needed to achieve the attack.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://blog.rust-lang.org/2026/05/25/cve-2026-5222/	Vendor Advisory
https://github.com/rust-lang/cargo/pull/17031	Issue Tracking Patch
https://groups.google.com/g/rustlang-security-announcements/c/SfUxOiIdY5s	Third Party Advisory Mailing List

Configurations

Configuration 1 (hide)

cpe:2.3:a:rust-lang:cargo:*:*:*:*:*:rust:*:*

History

01 Jun 2026, 17:56

Type	Values Removed	Values Added
References	~~() https://blog.rust-lang.org/2026/05/25/cve-2026-5222/ -~~	() https://blog.rust-lang.org/2026/05/25/cve-2026-5222/ - Vendor Advisory
References	~~() https://github.com/rust-lang/cargo/pull/17031 -~~	() https://github.com/rust-lang/cargo/pull/17031 - Issue Tracking, Patch
References	~~() https://groups.google.com/g/rustlang-security-announcements/c/SfUxOiIdY5s -~~	() https://groups.google.com/g/rustlang-security-announcements/c/SfUxOiIdY5s - Third Party Advisory, Mailing List
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 6.5
CPE		cpe:2.3:a:rust-lang:cargo::::::rust::*
First Time		Rust-lang Rust-lang cargo

25 May 2026, 10:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-25 10:16

Updated : 2026-06-01 17:56

NVD link : CVE-2026-5222

Mitre link : CVE-2026-5222

CVE.ORG link : CVE-2026-5222

JSON object : View

Products Affected

rust-lang

cargo

CWE

CWE-647

Use of Non-Canonical URL Paths for Authorization Decisions

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