CVE-2020-1045
Microsoft ASP.NET Core Security Feature Bypass Vulnerability
7.5CVSSHIGH
Description
<p>A security feature bypass vulnerability exists in the way Microsoft ASP.NET Core parses encoded cookie names.</p> <p>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.</p> <p>The security update addresses the vulnerability by fixing the way the ASP.NET Core cookie parser handles encoded names.</p>
CVSS Vector Breakdown
Exploitability
AV:NAttack VectorNetwork
AC:LAttack ComplexityLow
PR:NPrivileges RequiredNone
UI:NUser InteractionNone
Scope
S:UScopeUnchanged
Impact
C:NConfidentialityNone
I:HIntegrityHigh
A:NAvailabilityNone
Weaknesses
Affected Products
and 17 more affected products View all →
Exploitability
Official Patch Available
References
https://access.redhat.com/errata/RHSA-2020:3699
access.redhat.com
https://github.com/dotnet/core/blob/main/release-notes/3.1/3.1.8/3.1.8.md#changes-in-318
github.com
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5LN2FUVBSVPGK7AU3NMLO3YR6CGONQPB/
lists.fedoraproject.org
and 14 more references View all →
Timeline
Published
Sep 11, 2020
Last Updated
Feb 23, 2026
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