What is the CVSS score of CVE-2021-33723?

CVE-2021-33723 has a CVSS 3.1 base score of 6.5 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N. EPSS exploitation probability: 0.6%.

Is there a patch available for CVE-2021-33723?

Yes, a patch is available for CVE-2021-33723. Update the affected software to the latest version immediately.

Sinec Nms CVE-2021-33723

MEDIUM

Improper Authorization (CWE-285)

2021-10-12 productcert@siemens.com

Authentication Bypass Siemens Sinec Nms

6.5

CVSS 3.1 · NVD

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Vulnerability Assessment

Weakness	CWE CWE-285 OWASP Top 10:2025 A01:2025 - Broken Access Control ASVS 5.0 V8 - Authorization Authorization verification MITRE ATT&CK 1 technique across 1 tactic: Defense Evasion The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. Sign in to read
Impact	CVSS score of 6.5 (MEDIUM). Attack characteristics: network attack vector, low complexity, low privileges required, no user interaction not required.
Exploit ScenarioDerived	This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the medium-severity affected system.

This Month Plan within 30 days. Why: MEDIUM severity (CVSS 4.0-6.9).

Patch available 0.6% exploitation probability (EPSS)

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AnalysisAI

A vulnerability has been identified in SINEC NMS (All versions < V1.0 SP2 Update 1). Rated medium severity (CVSS 6.5), this vulnerability is remotely exploitable, low attack complexity.

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.

Affects your stack

Find out whether the stacks and servers you run are on an affected version.

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

This vulnerability is classified under CWE-285. A vulnerability has been identified in SINEC NMS (All versions < V1.0 SP2 Update 1). An authenticated attacker could change the user profile of any user without proper authorization. With this, the attacker could change the password of any user in the affected system. Affected products include: Siemens Sinec Nms.

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Exploit and PoC references, threat intelligence from 22 sources

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Severity by source

NVD PRIMARY 6.5 MEDIUM

AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

High

Availability

None

DescriptionNVD

A vulnerability has been identified in SINEC NMS (All versions < V1.0 SP2 Update 1). An authenticated attacker could change the user profile of any user without proper authorization. With this, the attacker could change the password of any user in the affected system.

Threat Intelligence Overview

EPSS Score

0.6%

Top 55% exploitable

Data Quality

2 sources

Confidence: Low

NVD

CVE.org

EPSS

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue

Severity MEDIUM

CISA KEV No

Public POC No

EPSS 0.6%

Patch available Yes

Active threat No

Deciding rule

MEDIUM severity (CVSS 4.0-6.9)

What every action level means

Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.

Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.

This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.

This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.

Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived

Scheduled

Exploitation· derived

None

System Exposure· derived

Open

Automatable· derived

Human Impact· derived

Medium

Priority Score

Low Medium High Critical

KEV: 0

EPSS: +1

CVSS: +32

PoC: 0

Weaponized: 0

Threat intel: 0

Gov advisory: 0

Attack Technique

Authentication Bypass CRITICAL

Authentication bypass attacks exploit flaws in the verification mechanisms that control access to systems and applications.

Affected Products (CPE)NVD

cpe:2.3:a:siemens:sinec_nms:*:*:*:*:*:*:*:*

cpe:2.3:a:siemens:sinec_nms:1.0:-:*:*:*:*:*:*

cpe:2.3:a:siemens:sinec_nms:1.0:sp1:*:*:*:*:*:*

cpe:2.3:a:siemens:sinec_nms:1.0:sp2:*:*:*:*:*:*

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Same weakness CWE-285 – Improper Authorization

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References

Advisories & patches

PATCH https://cert-portal.siemens.com/productcert/pdf/ssa-163251.pdf

Search Externally

GitHub PoC

Exploit-DB PacketStorm Snyk Rapid7 Nuclei Templates Trickest PoC

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