# GO-2026-5300 - Algernon: Auto-refresh SSE event server binds to all interfaces with Access-Control-Allow-Origin: * and…

Source: https://junglewise.ai/threats/go-2026-5300-algernon-auto-refresh-sse-event-server-binds-to-all-459dcf1f  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-25  
License: CC BY 4.0 with a link back

Severity: info · Published 2026-06-25

Algernon: Auto-refresh SSE event server binds to all interfaces with Access-Control-Allow-Origin: * and no authentication in github.com/xyproto/algernon

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

## Quick answers

**Is This vulnerability exploited in the wild?** No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.

**How severe is This vulnerability?** Informational severity, published 25 June 2026.

**Which products and versions are affected?** github.com/xyproto/algernon (Go) SEMVER:introduced=0,fixed=1.17.7.

**Is there a fix for This vulnerability?** Yes. github.com/xyproto/algernon (Go): upgrade to 1.17.7 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected?** Check whether you run github.com/xyproto/algernon (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/xyproto/algernon (Go): upgrade to 1.17.7 or later

  ```sh
  go get github.com/xyproto/algernon@v1.17.7
  ```


## Affected products

- github.com/xyproto/algernon (Go) SEMVER:introduced=0,fixed=1.17.7

## Related threats

- [xyproto Algernon source disclosure via NTFS filename manipulation](https://junglewise.ai/threats/cve-2026-52792-xyproto-algernon-source-disclosure-via-ntfs-filename-manipulation)
- [xyproto Algernon path traversal and RCE via Host header](https://junglewise.ai/threats/cve-2026-48126-xyproto-algernon-path-traversal-and-rce-via-host-header)
- [xyproto Algernon permissive CORS policy in SSE event server](https://junglewise.ai/threats/cve-2026-46431-xyproto-algernon-permissive-cors-policy-in-sse-event-server)
- [xyproto Algernon information disclosure in single-file mode](https://junglewise.ai/threats/cve-2026-45728-xyproto-algernon-information-disclosure-in-single-file-mode)
- [xyproto Algernon remote code execution via handler.lua path traversal](https://junglewise.ai/threats/cve-2026-45721-xyproto-algernon-remote-code-execution-via-handler-lua-path)