SeaweedFS up to 4.33 S3 API Gateway CopyObject/UploadPartCopy X-Amz-Copy-Source unrestricted upload

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.0$0-$5k0.59+

Summaryinfo

A vulnerability labeled as critical has been found in SeaweedFS up to 4.33. This affects the function CopyObject/UploadPartCopy of the component S3 API Gateway. The manipulation of the argument X-Amz-Copy-Source results in unrestricted upload. This vulnerability is known as CVE-2026-55874. It is possible to launch the attack remotely. No exploit is available.

Detailsinfo

A vulnerability was found in SeaweedFS up to 4.33. It has been classified as critical. Affected is the function CopyObject/UploadPartCopy of the component S3 API Gateway. The manipulation of the argument X-Amz-Copy-Source with an unknown input leads to a unrestricted upload vulnerability. CWE is classifying the issue as CWE-434. The product allows the attacker to upload or transfer files of dangerous types that can be automatically processed within the product's environment. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

SeaweedFS is a distributed storage system. Prior to 4.34, the S3 API gateway does not reject dot-dot path segments in the X-Amz-Copy-Source header used by CopyObject and UploadPartCopy, allowing an authenticated identity scoped to one bucket to read objects from other buckets through server-side copy. This issue is fixed in version 4.34.

The advisory is available at github.com. This vulnerability is traded as CVE-2026-55874 since 06/17/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1608.002 by the MITRE ATT&CK project.

Upgrading to version 4.34 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Unrestricted upload
CWE: CWE-434 / CWE-284 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Upgrade: SeaweedFS 4.34

Timelineinfo

06/17/2026 CVE reserved
07/08/2026 +21 days Advisory disclosed
07/08/2026 +0 days VulDB entry created
07/08/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-55874 (🔒)
GCVE (CVE): GCVE-0-2026-55874
GCVE (VulDB): GCVE-100-376890

Entryinfo

Created: 07/08/2026 17:28
Changes: 07/08/2026 17:28 (54)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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