Cargo can be coerced to share credentials between registries

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS 4.0

2.3 · CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N · score source

EPSS

• CVE-2026-5222: 0.48% estimated exploitation activity in the next 30 days; percentile 41.29 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

The Rust Security Response Team was notified that Cargo incorrectly normalized the URLs of third-party registries using the [sparse index protocol][1]. 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. This vulnerability is tracked as CVE-2026-5222. The severity of the vulnerability is low, due to the extremely niche requirements needed to achieve the attack. Overview Originally Cargo only supported storing a registry's index within git repositories. Most git hosting solutions allow accessing a git repository with or without the .git suffix, so Cargo mirrored this behavior when normalizing registry URLs. This allowed credentials for https://example.com/index to be used for https://example.com/index.git. This normalization was unintentionally applied to the new sparse indexes too. Sparse indexes can be hosted on…

Published by the source

26 Jun 2026, 21:47 UTC

Last modified by the source

26 Jun 2026, 21:47 UTC

Source last checked

26 Oct 2026, 15:42 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-p688-r7jv-fm6f

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# Patch Next advisory brief: CVE-2026-5222

Advisory: Cargo can be coerced to share credentials between registries
IDs: CVE-2026-5222, GHSA-p688-r7jv-fm6f
Record: https://patchnext.com/advisories/cve-2026-5222 (revision 1, source checked 26 Oct 2026, 15:42 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Low (CVSS 2.3)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: cargo 0.97.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- crates.io cargo: affected < 0.97.0; fixed in 0.97.0

## Suggested inspection (read-only)
- crates.io cargo: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on cargo.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-p688-r7jv-fm6f (GitHub-reviewed advisory GHSA-p688-r7jv-fm6f lists affected ranges: crates.io cargo >=0 <0.97.0)

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