CVE-2021-25661
No known exploitation. EPSS puts it in the 65th 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 has been identified in SIMATIC HMI Comfort Outdoor Panels V15 7\" & 15\" (incl. SIPLUS variants) (All versions < V15.1 Update 6), SIMATIC HMI Comfort Outdoor Panels V16 7\" & 15\" (incl. SIPLUS variants) (All versions < V16 Update 4), SIMATIC HMI Comfort Panels V15 4\" - 22\" (incl. SIPLUS variants) (All versions < V15.1 Update 6), SIMATIC HMI Comfort Panels V16 4\" - 22\" (incl. SIPLUS variants) (All versions < V16 Update 4), SIMATIC HMI KTP Mobile Panels V15 KTP400F, KTP700, KTP700F, KTP900 and KTP900F (All versions < V15.1 Update 6), SIMATIC HMI KTP Mobile Panels V16 KTP400F, KTP700, KTP700F, KTP900 and KTP900F (All versions < V16 Update 4), SIMATIC WinCC Runtime Advanced V15 (All versions < V15.1 Update 6), SIMATIC WinCC Runtime Advanced V16 (All versions < V16 Update 4). SmartVNC has an out-of-bounds memory access vulnerability that could be triggered on the client side when sending data from the server, which could result in a Denial-of-Service condition.
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
1.1% chance of exploitation activity in the next 30 days, which ranks it in the 65th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
4 events over 1847 days, from the signal feeds we watch.
- Patch availablerecord updated
- Publishedweakness classified
Affected products
- SIMATIC HMI Comfort Outdoor Panels V15 7\" & 15\" (incl. SIPLUS variants)ICS / OT / IoT
- SIMATIC HMI Comfort Outdoor Panels V16 7\" & 15\" (incl. SIPLUS variants)ICS / OT / IoT
- SIMATIC HMI Comfort Panels V15 4\" - 22\" (incl. SIPLUS variants)ICS / OT / IoT
- SIMATIC HMI Comfort Panels V16 4\" - 22\" (incl. SIPLUS variants)ICS / OT / IoT
- SIMATIC HMI KTP Mobile Panels V15 KTP400F, KTP700, KTP700F, KTP900 and KTP900FICS / OT / IoT
- SIMATIC HMI KTP Mobile Panels V16 KTP400F, KTP700, KTP700F, KTP900 and KTP900FICS / OT / IoT
- SIMATIC WinCC Runtime Advanced V15ICS / OT / IoT
- SIMATIC WinCC Runtime Advanced V16ICS / OT / IoT
And 10 more affected products. See all after sign-in
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
Sources
References in the record
- us-cert.cisa.gov/ics/advisories/icsa-21-131-12
- cert-portal.siemens.com/productcert/pdf/ssa-538778.pdf
- cert-portal.siemens.com/productcert/csaf/ssa-538778.json
And 19 more references. See all after sign-in
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