CVE-2026-33419
Received Received - Intake
LDAP Credential Brute-Force in MinIO STS Enables Unauthorized Access

Publication date: 2026-03-24

Last updated on: 2026-04-08

Assigner: GitHub, Inc.

Description
MinIO is a high-performance object storage system. Prior to RELEASE.2026-03-17T21-25-16Z, MinIO AIStor's STS (Security Token Service) AssumeRoleWithLDAPIdentity endpoint is vulnerable to LDAP credential brute-forcing due to two combined weaknesses: (1) distinguishable error responses that enable username enumeration, and (2) absence of rate limiting on authentication attempts. An unauthenticated network attacker can enumerate valid LDAP usernames and then perform unlimited password guessing to obtain temporary AWS-style STS credentials, gaining access to the victim's S3 buckets and objects. This issue has been patched in RELEASE.2026-03-17T21-25-16Z.
CVSS Scores
EPSS Scores
Probability:
Percentile:
Meta Information
Published
2026-03-24
Last Modified
2026-04-08
Generated
2026-06-16
AI Q&A
2026-03-24
EPSS Evaluated
2026-06-15
NVD
CVE-2026-33419
Affected Vendors & Products
Showing 1 associated CPE
Vendor Product Version / Range
minio minio to 2026-03-17t21-25-16z (exc)
Helpful Resources
Exploitability
CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-307 The product does not implement sufficient measures to prevent multiple failed authentication attempts within a short time frame.
CWE-204 The product provides different responses to incoming requests in a way that reveals internal state information to an unauthorized actor outside of the intended control sphere.
Attack-Flow Graph
AI Quick Actions
Instant insights powered by AI
Mitigation Strategies

I don't know

Executive Summary

This vulnerability affects MinIO AIStor's Security Token Service (STS) AssumeRoleWithLDAPIdentity endpoint. It arises from two main weaknesses: first, the system provides distinguishable error responses that allow an attacker to enumerate valid LDAP usernames; second, there is no rate limiting on authentication attempts. An unauthenticated attacker can exploit these weaknesses to guess passwords unlimitedly, eventually obtaining temporary AWS-style STS credentials.

With these credentials, the attacker can gain unauthorized access to the victim's S3 buckets and objects stored in MinIO.

This vulnerability was fixed in the MinIO release RELEASE.2026-03-17T21-25-16Z.

Impact Analysis

If exploited, this vulnerability allows an unauthenticated attacker to enumerate valid LDAP usernames and perform unlimited password guessing to obtain temporary security credentials.

This can lead to unauthorized access to your S3 buckets and stored objects, potentially resulting in data exposure, data theft, or data manipulation.

Such unauthorized access can compromise the confidentiality and integrity of your stored data.

Compliance Impact

I don't know

Detection Guidance

I don't know

Chat Assistant
Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-33419. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70
EPSS Chart