CVE-2021-20699
No known exploitation. EPSS puts it in the 76th percentile. No fix published yet.
What to do
No fixed build or workaround is published yet. Limit exposure and watch for a patch.
What it is
From the CVE record
Sharp NEC Displays ((UN462A R1.300 and prior to it, UN462VA R1.300 and prior to it, UN492S R1.300 and prior to it, UN492VS R1.300 and prior to it, UN552A R1.300 and prior to it, UN552S R1.300 and prior to it, UN552VS R1.300 and prior to it, UN552 R1.300 and prior to it, UN552V R1.300 and prior to it, UX552S R1.300 and prior to it, UX552 R1.300 and prior to it, V864Q R2.000 and prior to it, C861Q R2.000 and prior to it, P754Q R2.000 and prior to it, V754Q R2.000 and prior to it, C751Q R2.000 and prior to it, V984Q R2.000 and prior to it, C981Q R2.000 and prior to it, P654Q R2.000 and prior to it, V654Q R2.000 and prior to it, C651Q R2.000 and prior to it, V554Q R2.000 and prior to it, P404 R3.200 and prior to it, P484 R3.200 and prior to it, P554 R3.200 and prior to it, V404 R3.200 and prior to it, V484 R3.200 and prior to it, V554 R3.200 and prior to it, V404-T R3.200 and prior to it, V484-T R3.200 and prior to it, V554-T R3.200 and prior to it, C501 R2.000 and prior to it, C551 R2.000 and prior to it, C431 R2.000 and prior to it) allows an attacker a buffer overflow and to execute remote code by sending long parameters that contains specific characters in http request.
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
1.7% chance of exploitation activity in the next 30 days, which ranks it in the 76th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
4 events over 1645 days, from the signal feeds we watch.
- Record updated
- Publishedweakness classified, att&ck mapped
Affected products
- un462a firmwareHardware Firmware / printer-peripheral
- un462va firmwareHardware Firmware / printer-peripheral
- un492s firmwareHardware Firmware / printer-peripheral
- un492vs firmwareHardware Firmware / printer-peripheral
- un552a firmwareHardware Firmware / printer-peripheral
- un552s firmwareHardware Firmware / printer-peripheral
- un552vs firmwareHardware Firmware / printer-peripheral
- un552 firmwareHardware Firmware / printer-peripheral
- UN462AHardware Firmware / printer-peripheral
- UN462VAHardware Firmware / printer-peripheral
- UN492SHardware Firmware / printer-peripheral
- UN492VSHardware Firmware / printer-peripheral
- UN552AHardware Firmware / printer-peripheral
- UN552SHardware Firmware / printer-peripheral
- UN552VSHardware Firmware / printer-peripheral
- UN552Hardware Firmware / printer-peripheral
And 52 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:H/I:H/A:H
Scored 9.8 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 HighTotal information disclosure — all data in the component is compromised
- Integrity HighTotal loss of integrity — attacker can modify any data in the component
- 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.
- ExecutionT1059Command and Scripting Interpreterhigh confidence
- Initial AccessT1190Exploit Public-Facing Applicationhigh confidence
- Privilege EscalationT1068Exploitation for Privilege Escalationhigh confidence
Sources
Watch the software you run.
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We'll flag the next CVE, public exploit or patch for Un462a Firmware, not every advisory.
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