CVE-2021-26701
highpriority · track · 41EPSS 0.301 · 98 %ileEURUUSEPSS · scored 2026-10-27
.NET Core Remote Code Execution Vulnerability
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–critical · 6.4–9.8
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (29)
Products and version ranges known to be affected.
advisories (3)
Vendor and ecosystem advisories describing this.
- GHSA-ghhp-997w-qr28.NET Core Remote Code Execution Vulnerability2021-04-21ghsa · osvUS
.NET Core Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021-24112. ### Executive summary Microsoft is releasing this security advisory to provide information about a vulnerability in .NET 5.0, .NET Core 3.1, and .NET Core 2.1. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability. A remote code execution vulnerability exists in .NET 5 and .NET Core due to how text encoding is performed. ### Discussion Discussion for this issue can be found at dotnet/runtime#49377 ### Mitigation factors Microsoft has not identified any mitigating factors for this vulnerability. ### Affected software The vulnerable package is `System.Text.Encodings.Web` . Upgrading your package and redeploying your app should be sufficient to address this vulnerability. Vulnerable package versions: Any .NET 5, .NET Core, or .NET Framework based application that uses the System.Text.Encodings.Web package with a vulnerable version listed below. Package Name | Vulnerable Versions | Secure Versions -|-|- System.Text.Encodings.Web | 4.0.0 - 4.5.0 | 4.5.1 System.Text.Encodings.Web | 4.6.0-4.7.1 | 4.7.2 System.Text.Encodings.Web | 5.0.0 | 5.0.1 Please validate that each of the .NET versions you are using is in support. Security updates are only provided for supported .NET versions.
- BIT-dotnet-2021-26701.NET Core Remote Code Execution Vulnerability2024-03-06vendor · osvUS
.NET Core Remote Code Execution Vulnerability
- BIT-dotnet-sdk-2021-26701.NET Core Remote Code Execution Vulnerability2024-03-06vendor · osvUS
.NET Core Remote Code Execution Vulnerability
also known as (7)
Other names and identifiers for this entity.
- CNNVD-202102-685cnnvd
- EUVD-2021-0826enisa_euvd
- BDU:2021-00931fstec_bdu
- GHSA-ghhp-997w-qr28enisa_euvd
- BIT-dotnet-2021-26701osv
- BIT-dotnet-sdk-2021-26701osv
- GHSA-ghhp-997w-qr28osv
sources
Which sources assert this record, and when.
references (34)
External citations — patches, advisories, analysis.
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/S2AZOUKMCHT2WBHR7MYDTYXWOBHZW5P5/cnnvd
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TW3ZSJTTMZAFKGW7NJWTVVFZUYYU2SJZ/cnnvd
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UBOSSX7U6BSHV5RI74FCOW4ITJ5RRJR5/cnnvd
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WA5WQJVHUL5C4XMJTLY3C67R4WP35EF4/cnnvd
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XPUKFHIGP5YNJRRFWKDJ2XRS4WTFJNNK/cnnvd
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YLFATXASXW4OV2ZBSRP4G55HJH73QPBP/cnnvd
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/S2AZOUKMCHT2WBHR7MYDTYXWOBHZW5P5/cnnvd
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TW3ZSJTTMZAFKGW7NJWTVVFZUYYU2SJZ/cnnvd
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