Evidence used
- No CISA KEV confirmation is currently recorded.
- The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
- EPSS is 1.66% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2021
CVE-2021-20699High confidence
Sharp Display Solutions, Ltd. UN462A — Improper Neutralization of Special Elements used in a Command ('Command Injection')
Sharp Display Solutions, Ltd. · UN462A
9.8CriticalCVSS 3.1
Within 72 hours
Fix not verifiedCritical technical impact with a remotely reachable, unauthenticated path; no CISA KEV confirmation is currently recorded.
R
Open reassessment dashboard →Operational reassessment
Published severity in operational context
Published severityCritical→Operational priority:Critical, unchanged from published severity.unchanged
Compensating controls
- Restrict the affected network interface to trusted sources where business-safe.
- Monitor vendor guidance and exploitation sources for a material change.
Verification
- Confirm that the asset runs Sharp Display Solutions, Ltd. UN462A and falls inside the recorded affected range.
- Recheck the vendor advisory before scheduling a change because no verified fixed version is currently retained.
- Validate exposure, authentication requirements and compensating controls in the actual environment.
- Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Critical technical impact with a remotely reachable, unauthenticated path; no CISA KEV confirmation is currently recorded.
Fix not verified01
What, why and how
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.
What
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.
Why
Untrusted input reaches a command interpreter without sufficient validation or separation from command syntax.
How
An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
What
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.
Why
Untrusted input reaches a command interpreter without sufficient validation or separation from command syntax.
How
An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
02
Exploit reality and attack path
CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.
Observed exploitation No confirmed evidence
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.
Public PoC / exploit material None recorded
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.
- Likely attack path
- a network path → Improper Neutralization of Special Elements used in a Command ('Command Injection') → cause the confidentiality, integrity or availability impact described by the vendor
- Attack surface
- Network
- Privileges required
- None: unauthenticated exploitation is possible
- User interaction
- None
- Attack complexity
- Low: no specialised conditions are recorded
- Security boundary
- Unchanged: impact remains within the vulnerable component's security authority
- Weakness
?
CWE means Common Weakness Enumeration: a standard category for the underlying weakness. - CWE-77 ↗
CWE-77: Improper Neutralization of Special Elements used in a Command ('Command Injection'). The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when it is sent to a downstream component.
- CVSS vector
?
CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity. CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HCommon Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.
AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major loss.AHighAvailability impact: A successful attack can cause a major loss.- Post-exploitation / living off the land
- No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
03
Patch and workaround
Operational remediation based on structured source evidence.
- Status
?
Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change. - Fix not verified
- Affected
- UN462A: ≤ R1.300
- UN462VA: ≤ R1.300
- UN492S: ≤ R1.300
- UN492VS: ≤ R1.300
- UN552A: ≤ R1.300
- UN552S: ≤ R1.300
- UN552VS: ≤ R1.300
- UN552: ≤ R1.300
- UN552V: ≤ R1.300
- UX552S: ≤ R1.300
- UX552: ≤ R1.300
- V864Q: ≤ R2.000
- C861Q: ≤ R2.000
- P754Q: ≤ R2.000
- V754Q: ≤ R2.000
- C751Q: ≤ R2.000
- V984Q: ≤ R2.000
- C981Q: ≤ R2.000
- P654Q: ≤ R2.000
- V654Q: ≤ R2.000
- C651Q: ≤ R2.000
- V554Q: ≤ R2.000
- C501: ≤ R2.000
- C551: ≤ R2.000
- C431: ≤ R2.000
- P404: ≤ R3.201
- P484: ≤ R3.201
- P554: ≤ R3.201
- V404: ≤ R3.201
- V484: ≤ R3.201
- V554: ≤ R3.201
- V404-T: ≤ R3.201
- V484-T: ≤ R3.201
- V554-T: ≤ R3.201
- Fixed
- No fixed version is explicitly recorded in the structured CVE data.
- Action
- No verified patch reference is present in the current structured sources. Check the vendor advisory before making a change.
- Workaround
- No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04
Evidence and provenance
Published 7 Jun 2021 · Last source change 8 Dec 2025, 15:51 UTC · CWE-77 · Improper Neutralization of Special Elements used in a Command ('Command Injection')
CVE recordCVE.org · 5.2
CVSS sourceNIST NVD
EPSS source FIRST · tracked since 2026-08-14
?
The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.European sourceENISA EUVD · EUVD-2021-8114
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceNIST NVD
NVD statusNVD modified after enrichment
Core structured fields are present and their contributing authorities are shown above.
Material change intelligence
View recent updates ↗What changed after publication
No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.
Technical terms and abbreviations used in this report
- CVE
- Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
- CVSS
- Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
- EPSS
- Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
- CWE
- Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
- CNA
- CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
- CISA ADP
- Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
- NVD
- National Vulnerability Database: NIST's enrichment service for CVE records.
- CERT / CSIRT
- A computer security incident response team that publishes warnings or coordinates incident response.
- PoC
- Proof of concept: public material that demonstrates or helps reproduce exploitation.
- CSAF
- Common Security Advisory Framework: a machine-readable format for security advisories.
- LoTL
- Living off the land: abuse of legitimate tools or system functions during an attack.