Speech recovery via power-LED optical emanations
Published Aug 10, 2021 · Updated Jul 4, 2026
Information disclosure in Winner desktop speakers through 2021-08-09 allows remote attackers to recover speech via optical measurements. Audio-dependent power consumption modulates the directly connected power-indicator LED, and optical-audio transformation reconstructs speech from its intensity changes. Exploitation requires line of sight, a telescope, and an electro-optical sensor with sufficient sampling speed; the demonstrated consequence is speech disclosure.
Summary
What happened
Information disclosure in Winner desktop speakers through 2021-08-09 allows remote attackers to recover speech via optical measurements. Audio-dependent power consumption modulates the directly connected power-indicator LED, and optical-audio transformation reconstructs speech from its intensity changes. Exploitation requires line of sight, a telescope, and an electro-optical sensor with sufficient sampling speed; the demonstrated consequence is speech disclosure.
The record
- CVE
- CVE-2021-38365
- Published
- Aug 10, 2021
- Updated
- Jul 4, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- T1123
- Attack vector
- adjacent
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 10, 2021CVE publishedPublication date reported by the CVE source.
- Jul 4, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- Glowworm Attack research demonstrationfunctional · demonstrated
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Technologies
Your stack
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Your stack
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