CVE-2026-46430 Details
Description
Algernon is a small self-contained pure-Go web server. Prior to 1.17.7, the SSE event server bound to 0.0.0.0:5553 on Linux/macOS by default because the platform-dependent host default in engine/flags.go:39-46 set host = "" for non-Windows, and utils.JoinHostPort("", ":5553") resolves to ":5553". This vulnerability is fixed in 1.17.7.
A vulnerability in Algernon web server versions prior to 1.17.7 allows the Server-Sent Events (SSE) event server to bind to all network interfaces by default on Linux and macOS. This issue arises because the default host setting for non-Windows platforms is empty, causing the server to listen on every interface. As a result, a LAN peer can connect and access the file-change stream without any developer interaction. In contrast, the default behavior on Windows is to bind only to the loopback interface, providing a safer option.
Users can update to Algernon version 1.17.7 or later, where this vulnerability is fixed. Alternatively, the default event address can be manually set to 'localhost' to prevent external access.
Metrics
CVSS 4.0 Severity and Vector Strings:
VolerionCVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
Volerion
Assessed May 26, 2026CISA-ADP
Assessed May 26, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/xyproto/algernon/security/advisories/GHSA-gj84-924c-48fx | CISA-ADP | AdvisoryExploitRemedyVendor |
| https://github.com/xyproto/algernon/security/advisories/GHSA-gj84-924c-48fx | [email protected] | AdvisoryExploitRemedyVendor |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-1188 | Initialization of a Resource with an Insecure Default | [email protected] |
| CWE-668 | Exposure of Resource to Wrong Sphere | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| Algernon | <= 1.17.6 (semver) |
CPE
Remediation
| |
Change History
5 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jul 24, 2026 | CVE Translated | [email protected] |
| Jun 17, 2026 | CVE Modified | [email protected] |
| Jun 17, 2026 | CVE Modified | CISA-ADP |
| May 26, 2026 | CVE Modified | CISA-ADP |
| May 26, 2026 | New CVE Received | [email protected] |