Role escalation via omitted trust-policy validation
Published Aug 26, 2026 · Updated Aug 27, 2026
Incorrect authorization in SeaweedFS 4.39 and earlier allows remote authenticated users to assume unauthorized IAM roles through the S3 API. S3IAMIntegration.AuthenticateJWT validates and role-maps a bearer OIDC token but fails to invoke the web-identity trust-policy validator before returning the role principal. A valid federated OIDC token mapped to a role is required; attached role permissions then allow object reads, writes, or deletion.
Summary
What happened
Incorrect authorization in SeaweedFS 4.39 and earlier allows remote authenticated users to assume unauthorized IAM roles through the S3 API. S3IAMIntegration.AuthenticateJWT validates and role-maps a bearer OIDC token but fails to invoke the web-identity trust-policy validator before returning the role principal. A valid federated OIDC token mapped to a role is required; attached role permissions then allow object reads, writes, or deletion.
The record
- CVE
- CVE-2026-77298
- Published
- Aug 26, 2026
- Updated
- Aug 27, 2026
- Vendor
- SeaweedFS
- Product
- SeaweedFS
- Classifications
- CWE-863, T1078
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 26, 2026CVE publishedPublication date reported by the CVE source.
- Aug 27, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=< 4.40
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo