# CVE-2026-26190: Milvus authentication bypass in REST API and debug endpoints

Source: https://junglewise.ai/threats/cve-2026-26190-milvus-authentication-bypass-in-rest-api-and-debug-endpoints  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-02-11. Updated: 2026-07-06  
License: CC BY 4.0 with a link back

CVE-2026-26190 · Severity: critical · CVSS 9.8 · Published 2026-02-11

Milvus, an open-source vector database used for AI and machine learning applications, contains a critical security flaw where its management port (9091) is exposed without proper authentication. An attacker can exploit this to gain full control over the database, allowing them to steal sensitive data, delete entire collections, or create new administrative accounts. This could lead to a total compromise of the database system and any integrated AI services.

Technologies: [github.com/milvus-io/milvus (Go)](https://junglewise.ai/threats/technologies/github-com-milvus-io-milvus). Vendors: [Go](https://junglewise.ai/threats/vendors/go).

## Quick answers

**Is CVE-2026-26190 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-26190 being exploited in the wild.

**How severe is CVE-2026-26190?** Critical severity, with a CVSS score of 9.8, published 11 February 2026.

**Which products and versions are affected?** github.com/milvus-io/milvus (Go) SEMVER:introduced=0, SEMVER:introduced=0,fixed=2.5.27.

**Is there a fix for CVE-2026-26190?** Yes. github.com/milvus-io/milvus (Go): upgrade to 2.5.27 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-26190 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-26190?** Check whether you run github.com/milvus-io/milvus (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- github.com/milvus-io/milvus (Go): upgrade to 2.5.27 or later

  ```sh
  go get github.com/milvus-io/milvus@v2.5.27
  ```


## Technical details

Milvus suffers from two primary authentication bypasses on TCP port 9091. First, the '/expr' debug endpoint uses a predictable default token ('by-dev') to allow arbitrary Go expression evaluation, which can be leveraged for credential theft or arbitrary file writes via access log manipulation. Second, the full REST API ('/api/v1/*') is incorrectly registered on the metrics/management port without any authentication middleware, even when authentication is enabled on primary ports. A remote, unauthenticated attacker can reach this port to perform CRUD operations on data, manage user credentials, or trigger a denial of service. Patches are available in versions 2.5.27 and 2.6.10.

## Affected products

- Milvus-io Milvus < 2.5.27, >= 2.6.0, < 2.6.10

## Identifiers

- CVE-2026-26190
- GHSA-7ppg-37fh-vcr6
- GO-2026-4481

## Timeline

- 2026-02-11: advisory: GitHub Advisory published
- 2026-02-11: patched: Fixes released in versions 2.5.27 and 2.6.10
- 2026-02-13: disclosed: NVD publication date

## References

- [https://api.github.com/users/0x1f](https://api.github.com/users/0x1f)
- [https://github.com/0x1f](https://github.com/0x1f)
- [https://api.github.com/users/0x1f/gists%7B/gist_id%7D](https://api.github.com/users/0x1f/gists%7B/gist_id%7D)
- [https://api.github.com/users/0x1f/repos](https://api.github.com/users/0x1f/repos)
- [https://avatars.githubusercontent.com/u/214688736?v=4](https://avatars.githubusercontent.com/u/214688736?v=4)
- [https://api.github.com/users/0x1f/events%7B/privacy%7D](https://api.github.com/users/0x1f/events%7B/privacy%7D)

## Related threats

- [Milvus weak hash in RBAC Grantee ID Handler](https://junglewise.ai/threats/cve-2026-10814-milvus-weak-hash-in-rbac-grantee-id-handler)
- [GO-2025-4114 - Milvus Proxy has a Critical Authentication Bypass Vulnerability in github.com/milvus-io/milvus](https://junglewise.ai/threats/cve-2025-64513-milvus-proxy-has-a-critical-authentication-bypass-vulnerability)