How severe is CVE-2026-34204?

CVE-2026-34204 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability high.

Is CVE-2026-34204 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-34204?

CVE-2026-34204 affects Minio. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-34204?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-34204 have an EU (EUVD) identifier?

Yes. CVE-2026-34204 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17600.

When was CVE-2026-34204 published?

CVE-2026-34204 was published on 2026-03-31 and last updated on 2026-06-17.

CVE-2026-34204

CVE-2026-34204 is a high-severity vulnerability in Minio with a CVSS 3.x base score of 7.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-287.

Key facts

Severity: High (CVSS 3.x base score 7.1)
CVSS v4: 7.1
EPSS exploit prediction: 0% (3rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-17600
Weakness: CWE-287
Affected product: Minio
Published: 2026-03-31
Last modified: 2026-06-17

Description

MinIO is a high-performance object storage system. Prior to version RELEASE.2026-03-26T21-24-40Z, a flaw in extractMetadataFromMime() allows any authenticated user with s3:PutObject permission to inject internal server-side encryption metadata into objects by sending crafted X-Minio-Replication-* headers on a normal PutObject request. This issue has been patched in version RELEASE.2026-03-26T21-24-40Z.

Frequently asked questions

What is CVE-2026-34204?: MinIO is a high-performance object storage system. Prior to version RELEASE.2026-03-26T21-24-40Z, a flaw in extractMetadataFromMime() allows any authenticated user with s3:PutObject permission to inject internal server-side encryption metadata into objects by sending crafted X-Minio-Replication-* headers on a normal PutObject request. This issue has been patched in version RELEASE.2026-03-26T21-24-40Z.
How severe is CVE-2026-34204?: CVE-2026-34204 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability high.
Is CVE-2026-34204 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-34204?: CVE-2026-34204 affects Minio. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-34204?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-34204 have an EU (EUVD) identifier?: Yes. CVE-2026-34204 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17600.
When was CVE-2026-34204 published?: CVE-2026-34204 was published on 2026-03-31 and last updated on 2026-06-17.

References

https://github.com/minio/minio/security/advisories/GHSA-3rh2-v3gr-35p9

Affected products (1)

cpe:2.3:a:minio:minio:*:*:*:*:*:*:*:*

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