CVE-2021-26434 (GCVE-0-2021-26434)
Vulnerability from cvelistv5 – Published: 2021-09-15 11:23 – Updated: 2026-08-10 15:10
VLAI
EPSS
VEX
Title
Visual Studio Elevation of Privilege Vulnerability
Summary
Visual Studio Elevation of Privilege Vulnerability
Severity
CWE
- Elevation of Privilege
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://msrc.microsoft.com/update-guide/vulnerabi… | vendor-advisorypatch |
| https://portal.msrc.microsoft.com/en-US/security-… | x_refsource_MISCx_transferred |
| https://www.zerodayinitiative.com/advisories/ZDI-… | x_refsource_MISCx_transferred |
Impacted products
5 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Microsoft | Microsoft Visual Studio 2017 version 15.9 (includes 15.0 - 15.8) |
Affected:
15.9.0 , < 15.9.39
(custom)
|
guessed | |
| Microsoft | Microsoft Visual Studio 2019 version 16.11 (includes 16.0 - 16.10) |
Affected:
16.11.0 , < 16.11.3
(custom)
|
guessed | |
| Microsoft | Microsoft Visual Studio 2019 version 16.4 (includes 16.0 - 16.3) |
Affected:
16.0 , < 16.4.26
(custom)
|
guessed | |
| Microsoft | Microsoft Visual Studio 2019 version 16.7 (includes 16.0 – 16.6) |
Affected:
16.0.0 , < 16.7.19
(custom)
|
guessed | |
| Microsoft | Microsoft Visual Studio 2019 version 16.9 (includes 16.0 - 16.8) |
Affected:
15.0.0 , < 16.9.11
(custom)
|
guessed |
Date Public
2021-09-14 14:00
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"redhat_vex": {
"current_release_date": "2026-03-27T14:29:24+00:00",
"cve": "CVE-2021-26434",
"id": "CVE-2021-26434",
"initial_release_date": "2021-09-14T07:00:00+00:00",
"product_status:known_not_affected": "1",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "Visual Studio Elevation of Privilege Vulnerability",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2021/cve-2021-26434.json",
"version": "3"
}
}
}
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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