What’s Vulnerable › Vulnerabilities

CVE-2025-31489: MinIO performs incomplete signature validation for unsigned-trailer uploads

• Severity: high (CVSS 8.7 v4.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 2.5% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2025-04-03 · updated 2026-06-17
• Weakness: CWE-347

Description

MinIO is a High Performance Object Storage released under GNU Affero General Public License v3.0. The signature component of the authorization may be invalid, which would mean that as a client you can use any arbitrary secret to upload objects given the user already has prior WRITE permissions on the bucket. Prior knowledge of access-key, and bucket name this user might have access to - and an access-key with a WRITE permissions is necessary. However with relevant information in place, uploading random objects to buckets is trivial and easy via curl. This issue is fixed in RELEASE.2025-04-03T14-56-28Z.

Affected products

• minio: before RELEASE.2025-04-03T14-56-28Z

References

• https://github.com/minio/minio/pull/21103
• https://github.com/minio/minio/security/advisories/GHSA-wg47-6jq2-q2hh

Get alerted when CVE-2025-31489 or the next vulnerability affects your stack