CVE-2023-6545Network attack vector

Open redirect via user-controlled login URL parameter

Published Dec 14, 2023 · Updated Aug 27, 2024

Open redirect in Beckhoff authelia-bhf before 4.37.5 allows remote attackers to send users to arbitrary external sites through the login page. The default TwinCAT/BSD configuration trusts a user-controlled URL parameter as the destination of a link from the Authelia login page. Exploitation requires a user to follow the crafted link; the demonstrated consequence is redirection, not direct data access or code execution.

CVSS severity4.7
Medium
EPSS probability0.43%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Open redirect in Beckhoff authelia-bhf before 4.37.5 allows remote attackers to send users to arbitrary external sites through the login page. The default TwinCAT/BSD configuration trusts a user-controlled URL parameter as the destination of a link from the Authelia login page. Exploitation requires a user to follow the crafted link; the demonstrated consequence is redirection, not direct data access or code execution.

The record

CVE
CVE-2023-6545
Published
Dec 14, 2023
Updated
Aug 27, 2024
Vendor
Beckhoff Automation GmbH & Co. KG
Product
authelia-bhf
Classifications
CWE-601, T1566.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 14, 2023CVE publishedPublication date reported by the CVE source.
  2. Aug 27, 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=0 <4.37.5

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Beckhoff Automation GmbH & Co. KG · authelia-bhfversion=0 <4.37.5

Published CVSS scores

4.3Beckhoff Automation GmbH & Co. KGCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
4.7CERT VDECVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/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-601URL Redirection to Untrusted Site ('Open Redirect')
T1566.002Phishing: Spearphishing Link

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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