CVE-2021-20145Network attack vector

Cross-customer LAN access via exposed OpenVPN credentials

Published Dec 9, 2021 · Updated Aug 3, 2024

Improper access control in Gryphon Tower 04.0004.12 and earlier allows remote attackers to access other customers' LANs via HomeBound VPN. The router stores an OpenVPN configuration with credentials without protection, allowing those credentials to join the shared HomeBound service and expose LAN interfaces belonging to other subscribers. Exploitation requires obtaining the exposed configuration, after which the attacker gains adjacent-network reachability to connected devices and can target their services or configuration.

CVSS severity7.5
High
EPSS probability1.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper access control in Gryphon Tower 04.0004.12 and earlier allows remote attackers to access other customers' LANs via HomeBound VPN. The router stores an OpenVPN configuration with credentials without protection, allowing those credentials to join the shared HomeBound service and expose LAN interfaces belonging to other subscribers. Exploitation requires obtaining the exposed configuration, after which the attacker gains adjacent-network reachability to connected devices and can target their services or configuration.

The record

CVE
CVE-2021-20145
Published
Dec 9, 2021
Updated
Aug 3, 2024
Vendor
Gryphon Online Safety, Inc.
Product
Gryphon Tower
Classifications
CWE-287, T1133
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 9, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record 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=<= 04.0004.12 (Current)

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Gryphon Online Safety, Inc. · Gryphon Towerversion=<= 04.0004.12 (Current)

Published CVSS scores

7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
8.6TenableCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
5.0NIST NVDAV:N/AC:L/Au:N/C:P/I:N/A: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.

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

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-287Improper Authentication
T1133External Remote Services

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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