CVE-2026-46430: 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…

PriorityP419medium4.3CVSS 3.1

AVAACLPRNUINSUCLINAN

EPSS

0.20%

9.6th percentile

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.

Affected

2 ranges

Vendor	Product	Version range	Fixed in
github.com	xyproto_algernon	>= 0 < 1.17.7	1.17.7
xyproto	algernon	< 1.17.7	1.17.7

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