# CVE-2026-27607: RustFS: Missing Post Policy Validation leads to Arbitrary Object Write

Source: https://junglewise.ai/threats/cve-2026-27607-rustfs-missing-post-policy-validation-leads-to-arbitrary-object  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-02-25  
License: CC BY 4.0 with a link back

CVE-2026-27607 · Severity: low · CVSS 3.1 · Published 2026-02-25

RustFS: Missing Post Policy Validation leads to Arbitrary Object Write

Technologies: [rustfs (crates.io)](https://junglewise.ai/threats/technologies/rustfs). Vendors: [crates.io](https://junglewise.ai/threats/vendors/crates-io).

## Quick answers

**Is CVE-2026-27607 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-27607 being exploited in the wild.

**How severe is CVE-2026-27607?** Low severity, with a CVSS score of 3.1, published 25 February 2026.

**Which products and versions are affected?** rustfs (crates.io) SEMVER:introduced=1.0.0-alpha.56,fixed=1.0.0-alpha.83.

**Is there a fix for CVE-2026-27607?** Yes. rustfs (crates.io): upgrade to 1.0.0-alpha.83 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2026-27607?** Check whether you run rustfs (crates.io) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- rustfs (crates.io): upgrade to 1.0.0-alpha.83 or later

  ```sh
  cargo update -p rustfs
  ```


## Affected products

- rustfs (crates.io) SEMVER:introduced=1.0.0-alpha.56,fixed=1.0.0-alpha.83

## Identifiers

- CVE-2026-27607
- GHSA-w5fh-f8xh-5x3p

## Related threats

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- [RustFS Logs Sensitive Credentials in Plaintext](https://junglewise.ai/threats/cve-2026-24762-rustfs-logs-sensitive-credentials-in-plaintext)