CVE-2026-55473Network attack vectorHinoki check available

Authenticated SSRF via unchecked NAT64 destinations

Published Sep 21, 2026 · Updated Sep 21, 2026

SSRF in HomeBox before 0.26.0 allows remote authenticated users to access internal IPv4 services through NAT64 notifier URLs. The notifier URL validator treats IPv4 destinations embedded in 64:ff9b::/96 or 64:ff9b:1::/48 as safe instead of applying the default bogon and metadata checks. Exploitation requires NAT64/DNS64 egress; the test endpoint can return propagated responses that disclose internal data or temporary cloud credentials.

CVSS severity6.0
Medium
EPSS probability0.41%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

SSRF in HomeBox before 0.26.0 allows remote authenticated users to access internal IPv4 services through NAT64 notifier URLs. The notifier URL validator treats IPv4 destinations embedded in 64:ff9b::/96 or 64:ff9b:1::/48 as safe instead of applying the default bogon and metadata checks. Exploitation requires NAT64/DNS64 egress; the test endpoint can return propagated responses that disclose internal data or temporary cloud credentials.

The record

CVE
CVE-2026-55473
Published
Sep 21, 2026
Updated
Sep 21, 2026
Vendor
SysAdmins Media
Product
HomeBox
Classifications
CWE-918, T1552.005
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 21, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 21, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 0.26.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

SysAdmins Media · HomeBoxversion=< 0.26.0

Published CVSS scores

6.0GitHubCVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-918Server-Side Request Forgery (SSRF)
T1552.005Cloud Instance Metadata API

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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