CVE-2021-25659
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/t...
No known exploitation. EPSS puts it in the 62nd percentile. A vendor fix is available.
What to do
The vendor has published a fix. Version details are below where the sources state them.
What it is
From the CVE record
A vulnerability was identified in the Automation License Manager software that could be triggered by sending specially crafted packets to port 4410/tcp of an affected system. This could cause a denial-of-service preventing legitimate users from using the system. Siemens has released an update for the Automation License Manager 6 and recommends to update to the latest version. Siemens recommends specific countermeasures for products where updates are not, or not yet available.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
1.0% chance of exploitation activity in the next 30 days, which ranks it in the 62nd percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
5 events over 1199 days, from the signal feeds we watch.
- Patch availablerecord updated
- Publishedweakness classified, att&ck mapped
Affected products
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Scored 7.5 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality NoneNo confidentiality impact
- Integrity NoneNo integrity impact
- Availability HighTotal denial of service — the component is completely unavailable
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
Sources
References in the record
- cert-portal.siemens.com/productcert/csaf/ssa-158827.json
- cert-portal.siemens.com/productcert/txt/ssa-158827.txt
- cert-portal.siemens.com/productcert/pdf/ssa-158827.pdf
And 10 more references. See all after sign-in
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