CVE-2021-26701 — Vulnerability in System.Text.Encodings.Web — CVE...
.NET Core Remote Code Execution Vulnerability
Summary
Advisory Timeline
- First published April 21, 2021 (2000 days ago).
- Last revised December 7, 2024 — 1325 days after initial publication.
Remediation
Upgrade to the fixed version using your package manager.
dotnet add package System.Text.Encodings.Web --version 4.5.1
dotnet add package System.Text.Encodings.Web --version 4.7.2
dotnet add package System.Text.Encodings.Web --version 5.0.1
After upgrading, run your dependency scanner again to confirm the vulnerability is resolved.
Affected Packages (3)
Affects 1 ecosystem: nuget (1).
| Package | Ecosystem | Affected | Fixed In |
|---|---|---|---|
| System.Text.Encodings.Web | nuget | 4.0.0, 4.0.1, 4.3.0, 4.3.0-preview1-24530-04 (+8 more) | 4.5.1 |
| System.Text.Encodings.Web | nuget | 4.6.0, 4.7.0, 4.7.1 | 4.7.2 |
| System.Text.Encodings.Web | nuget | 5.0.0 | 5.0.1 |
CVSS Score Breakdown
What the CVSS (Common Vulnerability Scoring System) 9.8 score means for each attack dimension.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
References
- https://nvd.nist.gov/vuln/detail/CVE-2021-26701ADVISORY
- https://github.com/dotnet/announcements/issues/178WEB
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/S2AZOUKMCHT2WBHR7MYDTYXWOBHZW5P5WEB
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TW3ZSJTTMZAFKGW7NJWTVVFZUYYU2SJZWEB
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UBOSSX7U6BSHV5RI74FCOW4ITJ5RRJR5WEB
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WA5WQJVHUL5C4XMJTLY3C67R4WP35EF4WEB
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XPUKFHIGP5YNJRRFWKDJ2XRS4WTFJNNKWEB
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YLFATXASXW4OV2ZBSRP4G55HJH73QPBPWEB
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/S2AZOUKMCHT2WBHR7MYDTYXWOBHZW5P5WEB
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TW3ZSJTTMZAFKGW7NJWTVVFZUYYU2SJZWEB
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UBOSSX7U6BSHV5RI74FCOW4ITJ5RRJR5WEB
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/WA5WQJVHUL5C4XMJTLY3C67R4WP35EF4WEB
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/XPUKFHIGP5YNJRRFWKDJ2XRS4WTFJNNKWEB
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/YLFATXASXW4OV2ZBSRP4G55HJH73QPBPWEB
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-26701WEB
Frequently Asked Questions
- What is CVE-2021-26701?
- .NET Core Remote Code Execution Vulnerability This vulnerability has been assigned a severity rating of CRITICAL (CVSS score: 9.8/10).
- How do I check if my project is affected by CVE-2021-26701?
- CVE-2021-26701 affects System.Text.Encodings.Web. Use GeekWala's free vulnerability scanner to check your dependencies against CVE-2021-26701 and 200,000+ other known vulnerabilities.
Severity & Exploitability
Exploitation is straightforward and causes maximum impact. Patch immediately.
Also Known As
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