CVE-2025-31489: MinIO performs incomplete signature validation for unsigned-trailer uploads
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.
Classification
CVE ID: CVE-2025-31489
CVSS Base Severity: HIGH
CVSS Base Score: 8.7
CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
Affected Products
Vendor: minio
Product: minio
Nuclei Template
http/cves/2025/CVE-2025-31489.yaml
Exploit Prediction Scoring System (EPSS)
EPSS Score: 1.47% (probability of being exploited)
EPSS Percentile: 79.93% (scored less or equal to compared to others)
EPSS Date: 2025-05-02 (when was this score calculated)
References
https://nvd.nist.gov/vuln/detail/CVE-2025-31489https://github.com/minio/minio/security/advisories/GHSA-wg47-6jq2-q2hh
https://github.com/minio/minio/pull/21103