Memory corruption via undersized WinBlast output buffer
Published Apr 6, 2026 · Updated Apr 6, 2026
Buffer over-read in the WinBlast driver in Qualcomm Snapdragon allows local users to trigger memory corruption during output retrieval. The driver retrieves an output buffer without adequately validating its supplied size, allowing reads beyond the intended boundary. Local low-privileged access is required, and Qualcomm has not disclosed whether successful exploitation exposes data, executes code, or crashes a device.
Summary
What happened
Buffer over-read in the WinBlast driver in Qualcomm Snapdragon allows local users to trigger memory corruption during output retrieval. The driver retrieves an output buffer without adequately validating its supplied size, allowing reads beyond the intended boundary. Local low-privileged access is required, and Qualcomm has not disclosed whether successful exploitation exposes data, executes code, or crashes a device.
The record
- CVE
- CVE-2026-21371
- Published
- Apr 6, 2026
- Updated
- Apr 6, 2026
- Vendor
- Qualcomm
- Product
- Snapdragon
- Classifications
- CWE-126
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Apr 6, 2026CVE publishedPublication date reported by the CVE source.
- Apr 6, 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?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=AQT1000
- Affected versionversion=Cologne
- Affected versionversion=FastConnect 6200
- Affected versionversion=FastConnect 6700
- Affected versionversion=FastConnect 6800
- Affected versionversion=FastConnect 6900
- Affected versionversion=FastConnect 7800
- Affected versionversion=QCA0000
- Affected versionversion=QCA6391
- Affected versionversion=QCA6420
- Affected versionversion=QCA6430
- Affected versionversion=QCM5430
- Affected versionversion=QCM6490
- Affected versionversion=Qualcomm Video Collaboration VC3 Platform
- Affected versionversion=SC8380XP
- Affected versionversion=SM6250
- Affected versionversion=Snapdragon 460 Mobile Platform
- Affected versionversion=Snapdragon 662 Mobile Platform
- Affected versionversion=Snapdragon 7c Compute Platform
- Affected versionversion=Snapdragon 7c Gen 2 Compute Platform "Rennell Pro"
- Affected versionversion=Snapdragon 7c+ Gen 3 Compute
- Affected versionversion=Snapdragon 8c Compute Platform "Poipu Lite"
- Affected versionversion=Snapdragon 8c Compute Platform (SC8180XP-AD) "Poipu Lite"
- Affected versionversion=Snapdragon 8cx Compute Platform
- Affected versionversion=Snapdragon 8cx Compute Platform "Poipu Pro"
- Affected versionversion=Snapdragon 8cx Gen 2 5G Compute Platform
- Affected versionversion=Snapdragon 8cx Gen 2 5G Compute Platform "Poipu Pro"
- Affected versionversion=Snapdragon 8cx Gen 3 Compute Platform
- Affected versionversion=WCD9340
- Affected versionversion=WCD9341
- Affected versionversion=WCD9370
- Affected versionversion=WCD9375
- Affected versionversion=WCD9378C
- Affected versionversion=WCD9380
- Affected versionversion=WCD9385
- Affected versionversion=WCN3950
- Affected versionversion=WCN3988
- Affected versionversion=WSA8810
- Affected versionversion=WSA8815
- Affected versionversion=WSA8830
- Affected versionversion=WSA8835
- Affected versionversion=WSA8840
- Affected versionversion=WSA8845
- Affected versionversion=WSA8845H
- Affected versionversion=X2000077
- Affected versionversion=X2000086
- Affected versionversion=X2000090
- Affected versionversion=X2000092
- Affected versionversion=X2000094
- Affected versionversion=XG101002
- Affected versionversion=XG101032
- Affected versionversion=XG101039
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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