CVE-2020-1045 — Vulnerability in...

HIGH

Cookie parsing failure

Published May 24, 2022Updated November 29, 2024Source: osv

Summary

A security feature bypass vulnerability exists in the way Microsoft ASP.NET Core parses encoded cookie names.The ASP.NET Core cookie parser decodes entire cookie strings which could allow a malicious attacker to set a second cookie with the name being percent encoded.The security update addresses the vulnerability by fixing the way the ASP.NET Core cookie parser handles encoded names., aka 'Microsoft ASP.NET Core Security Feature Bypass Vulnerability'.

Advisory Timeline

First published May 24, 2022 (1602 days ago).
Last revised November 29, 2024 — 920 days after initial publication.

Remediation

Upgrade to the fixed version using your package manager.

NuGet

Update Microsoft.AspNetCore.App.Runtime.win-x86 to 3.1.8 or later

dotnet add package Microsoft.AspNetCore.App.Runtime.win-x86 --version 3.1.8

NuGet

Update Microsoft.Owin to 4.1.1 or later

dotnet add package Microsoft.Owin --version 4.1.1

NuGet

Update Microsoft.AspNetCore.App.Runtime.win-arm to 3.1.8 or later

dotnet add package Microsoft.AspNetCore.App.Runtime.win-arm --version 3.1.8

NuGet

Update Microsoft.AspNetCore.App.Runtime.win-arm64 to 3.1.8 or later

dotnet add package Microsoft.AspNetCore.App.Runtime.win-arm64 --version 3.1.8

NuGet

Update Microsoft.AspNetCore.App.Runtime.linux-arm to 3.1.8 or later

dotnet add package Microsoft.AspNetCore.App.Runtime.linux-arm --version 3.1.8

NuGet

Update Microsoft.AspNetCore.App.Runtime.linux-x64 to 3.1.8 or later

dotnet add package Microsoft.AspNetCore.App.Runtime.linux-x64 --version 3.1.8

NuGet

Update Microsoft.AspNetCore.App to 2.1.22 or later

dotnet add package Microsoft.AspNetCore.App --version 2.1.22

NuGet

Update Microsoft.AspNetCore.App.Runtime.linux-musl-x64 to 3.1.8 or later

dotnet add package Microsoft.AspNetCore.App.Runtime.linux-musl-x64 --version 3.1.8

NuGet

Update Microsoft.AspNetCore.App.Runtime.linux-arm64 to 3.1.8 or later

dotnet add package Microsoft.AspNetCore.App.Runtime.linux-arm64 --version 3.1.8

NuGet

Update Microsoft.AspNetCore.Http to 2.1.22 or later

dotnet add package Microsoft.AspNetCore.Http --version 2.1.22

NuGet

Update Microsoft.AspNetCore.App.Runtime.win-x64 to 3.1.8 or later

dotnet add package Microsoft.AspNetCore.App.Runtime.win-x64 --version 3.1.8

NuGet

Update Microsoft.AspNetCore.App.Runtime.osx-x64 to 3.1.8 or later

dotnet add package Microsoft.AspNetCore.App.Runtime.osx-x64 --version 3.1.8

NuGet

Update Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 to 3.1.8 or later

dotnet add package Microsoft.AspNetCore.App.Runtime.linux-musl-arm64 --version 3.1.8

After upgrading, run your dependency scanner again to confirm the vulnerability is resolved.

Affected Packages (13)

Affects 1 ecosystem: nuget (13).

Package	Ecosystem	Affected	Fixed In
Microsoft.AspNetCore.App.Runtime.win-x86	nuget	3.1.0, 3.1.1, 3.1.2, 3.1.3 (+4 more)	3.1.8
Microsoft.Owin	nuget	1.1.0-beta1, 1.1.0-beta2, 2.0.0, 2.0.0-rc1 (+17 more)	4.1.1
Microsoft.AspNetCore.App.Runtime.win-arm	nuget	3.1.0, 3.1.1, 3.1.2, 3.1.3 (+4 more)	3.1.8
Microsoft.AspNetCore.App.Runtime.win-arm64	nuget	3.1.5, 3.1.6, 3.1.7	3.1.8
Microsoft.AspNetCore.App.Runtime.linux-arm	nuget	3.1.0, 3.1.1, 3.1.2, 3.1.3 (+4 more)	3.1.8
Microsoft.AspNetCore.App.Runtime.linux-x64	nuget	3.1.0, 3.1.1, 3.1.2, 3.1.3 (+4 more)	3.1.8
Microsoft.AspNetCore.App	nuget	2.1.0, 2.1.0-preview1-final, 2.1.0-preview2-final, 2.1.0-rc1-final (+21 more)	2.1.22
Microsoft.AspNetCore.App.Runtime.linux-musl-x64	nuget	3.1.0, 3.1.1, 3.1.2, 3.1.3 (+4 more)	3.1.8
Microsoft.AspNetCore.App.Runtime.linux-arm64	nuget	3.1.0, 3.1.1, 3.1.2, 3.1.3 (+4 more)	3.1.8
Microsoft.AspNetCore.Http	nuget	0.0.1-alpha, 1.0.0, 1.0.0-rc2-final, 1.0.1 (+18 more)	2.1.22
Microsoft.AspNetCore.App.Runtime.win-x64	nuget	3.1.0, 3.1.1, 3.1.2, 3.1.3 (+4 more)	3.1.8
Microsoft.AspNetCore.App.Runtime.osx-x64	nuget	3.1.0, 3.1.1, 3.1.2, 3.1.3 (+4 more)	3.1.8
Microsoft.AspNetCore.App.Runtime.linux-musl-arm64	nuget	3.1.0, 3.1.1, 3.1.2, 3.1.3 (+4 more)	3.1.8

CVSS Score Breakdown

What the CVSS (Common Vulnerability Scoring System) 7.5 score means for each attack dimension.

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

High

Availability

None

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

References

Frequently Asked Questions

What is CVE-2020-1045?: Cookie parsing failure This vulnerability has been assigned a severity rating of HIGH (CVSS score: 7.5/10).
How do I check if my project is affected by CVE-2020-1045?: CVE-2020-1045 affects Microsoft.AspNetCore.App.Runtime.win-x86, Microsoft.Owin and Microsoft.AspNetCore.App.Runtime.win-arm (and 10 more). Use GeekWala's free vulnerability scanner to check your dependencies against CVE-2020-1045 and 200,000+ other known vulnerabilities.

Severity & Exploitability

CVSS Score

7.5

High exploitability or significant impact. Prioritize remediation within days.

Also Known As

GHSA-hxrm-9w7p-39cc

BIT-aspnet-core-2020-1045

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