CVE-2023-5222Public exploitNetwork attack vector

Unauthenticated administrative access via embedded credentials

Published Sep 27, 2023 · Updated Aug 2, 2024

Hard-coded credentials in the web interface of Viessmann Vitogate 300 2.1.3.0 and earlier allow remote attackers to gain administrative access. The isValidUser function in /cgi-bin/vitogate.cgi accepts two embedded administrator account pairs, including a hidden account that cannot be removed or have its password changed. Network reachability of the integrated web server is sufficient; successful sign-in exposes the full management interface and its configuration functions.

CVSS severity9.3
Critical
EPSS probability74.52%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Hard-coded credentials in the web interface of Viessmann Vitogate 300 2.1.3.0 and earlier allow remote attackers to gain administrative access. The isValidUser function in /cgi-bin/vitogate.cgi accepts two embedded administrator account pairs, including a hidden account that cannot be removed or have its password changed. Network reachability of the integrated web server is sufficient; successful sign-in exposes the full management interface and its configuration functions.

The record

CVE
CVE-2023-5222
Published
Sep 27, 2023
Updated
Aug 2, 2024
Vendor
Viessmann
Product
Vitogate 300
Classifications
CWE-259, CWE-798, T1078.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 27, 2023CVE publishedPublication date reported by the CVE source.
  2. Aug 2, 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=2.1.0
  2. Affected versionversion=2.1.1
  3. Affected versionversion=2.1.2
  4. Affected versionversion=2.1.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Viessmann · Vitogate 300version=2.1.0; version=2.1.1; version=2.1.2; version=2.1.3

Published CVSS scores

9.3Carrier Product SecurityCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
5.8VulDBAV:A/AC:L/Au:N/C:P/I:P/A:P
6.3VulDBCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

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 exploitPublished

Weakness, pattern, technique

CWE-259Use of Hard-coded Password
CWE-798Use of Hard-coded Credentials
T1078.001Valid Accounts: Default Accounts

Public exploit references

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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