CVE-2021-26434 json
Visual Studio Elevation of Privilege Vulnerability
published 2021-09-15 5 y ago modified 2026-08-10 2 mo ago also EUVD-2021-13239
- cvss
- 7.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.9%
- EPSS 0.9% chance of exploitation in 30 days, percentile 59%
- public exploits
- 0
- none known
Summary
Visual Studio Elevation of Privilege Vulnerability
Patch / fix
- Microsoft Microsoft Visual Studio 2017 version 15.9 (includes 15.0 - 15.8) 15.9.39
- Microsoft Microsoft Visual Studio 2019 version 16.11 (includes 16.0 - 16.10) 16.11.3
- Microsoft Microsoft Visual Studio 2019 version 16.4 (includes 16.0 - 16.3) 16.4.26
- Microsoft Microsoft Visual Studio 2019 version 16.7 (includes 16.0 – 16.6) 16.7.19
- Microsoft Microsoft Visual Studio 2019 version 16.9 (includes 16.0 - 16.8) 16.9.11
Exploit prediction
0.89% chance of exploitation in the next 30 days, higher than 59% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C |
| CNA | 3.1 | 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 7.2 | AV:L/AC:L/Au:N/C:C/I:C/A:C |
Affected products
- Microsoft Microsoft Visual Studio 2017 version 15.9 (includes 15.0 - 15.8)
- Microsoft Microsoft Visual Studio 2019 version 16.11 (includes 16.0 - 16.10)
- Microsoft Microsoft Visual Studio 2019 version 16.4 (includes 16.0 - 16.3)
- Microsoft Microsoft Visual Studio 2019 version 16.7 (includes 16.0 – 16.6)
- Microsoft Microsoft Visual Studio 2019 version 16.9 (includes 16.0 - 16.8)
Classification
- Weakness
-
- CWE-732 Incorrect Permission Assignment for Critical Resource
References
-
msrc.microsoft.com
/update-guide/vulnerability/CVE-2021-26434
vendor-advisory, patch
-
portal.msrc.microsoft.com
/en-US/security-guidance/advisory/CVE-2021-26434
patch, vendor-advisory
-
zerodayinitiative.com
/advisories/ZDI-21-1077/
third-party-advisory, vdb-entry
Sources
- CVE List CVE-2021-26434
- NVD CVE-2021-26434
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.