CVE-2020-25239Network attack vector

Authenticated rogue-server addition via special URLs

Published Mar 15, 2021 · Updated Aug 4, 2024

Incorrect authorization in Siemens SINEMA Remote Connect Server before 3.0 allows remote authenticated users to add a rogue UMC server. The web server accepts special URLs from unprivileged accounts without enforcing authorization before changing UMC authorization-server settings. Any unprivileged account can alter the trusted authentication path, enabling a rogue server to affect the confidentiality, integrity, and availability of managed access.

CVSS severity8.8
High
EPSS probability0.94%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Incorrect authorization in Siemens SINEMA Remote Connect Server before 3.0 allows remote authenticated users to add a rogue UMC server. The web server accepts special URLs from unprivileged accounts without enforcing authorization before changing UMC authorization-server settings. Any unprivileged account can alter the trusted authentication path, enabling a rogue server to affect the confidentiality, integrity, and availability of managed access.

The record

CVE
CVE-2020-25239
Published
Mar 15, 2021
Updated
Aug 4, 2024
Vendor
Siemens
Product
SINEMA Remote Connect Server
Classifications
CWE-863, T1556
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Mar 15, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 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=All versions < V3.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Siemens · SINEMA Remote Connect Serverversion=All versions < V3.0

Published CVSS scores

8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
6.5NIST NVDAV:N/AC:L/Au:S/C:P/I:P/A:P

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-863Incorrect Authorization
T1556Modify Authentication Process

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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