Description
A flaw was found in the signature verification logic of noobaa-core, the core component of the NooBaa Multicloud Object Gateway. The issue occurs when the service processes S3 presigned URLs using Signature Version 4 (SigV4). Due to improper validation, the service fails to reject requests containing unsigned x-amz- headers, instead simply dropping them from the signature calculation. This allows an attacker who possesses a valid presigned PUT URL to add an unsigned x-amz-copy-source header, effectively converting a simple upload into a CopyObject operation. This can lead to unauthorized access and copying of any data the original signer is permitted to reach across the entire storage system.
References2
Metrics
- CVSS 3.1
-
7.1
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N - EPSS — exploit probability
- 0% percentile: 14 · as of 8 November 2026
- CWE
- CWE-347
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