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TI-2021-07791 Aliases CVE-2021-25659GHSA-qhxf-2fw5-w33w

Uncontrolled resource consumption in Siemens Automation License Manager 5

Priority LOW 35CWE-400Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-400.

Summary

A vulnerability has been identified in Automation License Manager 5 (All versions), Automation License Manager 6 (All versions < V6.0 SP9 Update 2). Sending specially crafted packets to port 4410/tcp of an affected system could lead to extensive memory being consumed and as such could cause a denial-of-service preventing legitimate users from using the system.

Why it matters now

EPSS 0.01037 64th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
SiemensAutomation License Manager 5All versions—No fix listedCNA
SiemensAutomation License Manager 6All versions < V6.0 SP9 Update 2—No fix listedCNA
  • Automation License Manager 5 VendorSiemens Affected All versions Fixed in — No fix listed CNA
  • Automation License Manager 6 VendorSiemens Affected All versions < V6.0 SP9 Update 2 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:siemens:automation_license_manager:*:*:*:*:*:*:*:*5.0.0 to before 6.0.9VulnerableSiemens
  • cpe:2.3:a:siemens:automation_license_manager:*:*:*:*:*:*:*:* Versions 5.0.0 to before 6.0.9 Vulnerable ·Siemens

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-25659
  2. 2026-10-03 Alias added: GHSA-qhxf-2fw5-w33w

References

Patch 1

  • TI-2022-21296 Path traversal in Siemens Automation License Manager V5 CVSS 3.1CRITICAL 9.8
  • TI-2018-08180 Path traversal in Siemens Automation License Manager 5, Automation License Manager 6 CVSS 3.0HIGH 8.8
  • TI-2016-07037 Siemens Automation License Manager (ALM) before 5.3 SP3 allows remote attackers to write… CVSS 3.0CRITICAL 9.1
  • TI-2022-21295 A vulnerability has been identified in Automation License Manager V5 (All versions)… CVSS 3.1HIGH 8.2
  • TI-2011-03900 Multiple buffer overflows in Siemens Automation License Manager (ALM) 4.0 through… CVSS 2.0HIGH 7.5
  • TI-2016-07035 Siemens Automation License Manager (ALM) before 5.3 SP3 Update 1 allows remote attackers… CVSS 3.0HIGH 7.5
See all 13 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences