CVE-2026-46430

MEDIUM

Algernon: Auto-refresh SSE event server binds to all interfaces by default on Linux/macOS

Title source: cna
STIX 2.1

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.

References (1)

Core 1
Core References

Scores

CVSS v3 4.3
EPSS 0.0020
EPSS Percentile 9.5%
Attack Vector ADJACENT_NETWORK
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

CISA SSVC

Vulnrichment
Exploitation poc
Automatable no
Technical Impact partial

Details

CWE
CWE-1188 CWE-668
Status published
Products (1)
xyproto/algernon < 1.17.7
Published May 26, 2026
Tracked Since May 26, 2026