CVE-2026-46430: CWE-668: Exposure of Resource to Wrong Sphere in xyproto algernon
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.
AI Analysis
Technical Summary
The vulnerability in xyproto algernon prior to version 1.17.7 arises because the SSE event server binds to 0.0.0.0:5553 on Linux and macOS by default. This occurs because the platform-dependent host default in engine/flags.go sets the host to an empty string for non-Windows systems, which resolves to binding on all interfaces. This behavior exposes the SSE event server to unintended network spheres, classified under CWE-668 (Exposure of Resource to Wrong Sphere) and CWE-1188. The vulnerability has been addressed and fixed in version 1.17.7.
Potential Impact
The vulnerability allows the SSE event server to be accessible on all network interfaces by default on Linux and macOS, potentially exposing it to unauthorized access from unintended network sources. The CVSS score of 4.3 reflects limited confidentiality impact without affecting integrity or availability. There are no known exploits in the wild at this time.
Mitigation Recommendations
Upgrade to xyproto algernon version 1.17.7 or later, where this issue is fixed. Since no official patch link or remediation level is explicitly provided, users should verify the update availability from the vendor's official release channels. No additional mitigation steps are indicated.
CVE-2026-46430: CWE-668: Exposure of Resource to Wrong Sphere in xyproto algernon
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.
CVSS v3.1
Score 4.3medium
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability in xyproto algernon prior to version 1.17.7 arises because the SSE event server binds to 0.0.0.0:5553 on Linux and macOS by default. This occurs because the platform-dependent host default in engine/flags.go sets the host to an empty string for non-Windows systems, which resolves to binding on all interfaces. This behavior exposes the SSE event server to unintended network spheres, classified under CWE-668 (Exposure of Resource to Wrong Sphere) and CWE-1188. The vulnerability has been addressed and fixed in version 1.17.7.
Potential Impact
The vulnerability allows the SSE event server to be accessible on all network interfaces by default on Linux and macOS, potentially exposing it to unauthorized access from unintended network sources. The CVSS score of 4.3 reflects limited confidentiality impact without affecting integrity or availability. There are no known exploits in the wild at this time.
Mitigation Recommendations
Upgrade to xyproto algernon version 1.17.7 or later, where this issue is fixed. Since no official patch link or remediation level is explicitly provided, users should verify the update availability from the vendor's official release channels. No additional mitigation steps are indicated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-05-13T22:18:22.830Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a15d22e891d628fdc60089a
Added to database: 5/26/2026, 5:02:38 PM
Last enriched: 5/26/2026, 5:20:14 PM
Last updated: 5/26/2026, 9:50:05 PM
Views: 2
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