cbcvebase.
CVE-2020-1045
published 2020-09-11

CVE-2020-1045: 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…

PriorityP344high7.5CVSS 3.1
AVNACLPRNUINSUCNIHAN
EPSS
5.97%
92.5th percentile
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.

Affected

28 ranges· showing 25
VendorProductVersion rangeFixed in
fedoraprojectfedora
fedoraprojectfedora
microsoftasp.net_core2.1 – 2.1.21
microsoftasp.net_core>= 3.1 < 3.1.83.1.8
microsoftasp.net_core_2.1>= 2.0 < publicationpublication
microsoftasp.net_core_3.1>= 3.0 < publicationpublication
microsoftmicrosoft.aspnetcore.app.runtime.linux-arm>= 3.1.0 < 3.1.83.1.8
microsoftmicrosoft.aspnetcore.app.runtime.linux-arm64>= 3.1.0 < 3.1.83.1.8
microsoftmicrosoft.aspnetcore.app.runtime.linux-musl-arm64>= 3.1.0 < 3.1.83.1.8
microsoftmicrosoft.aspnetcore.app.runtime.linux-musl-x64>= 3.1.0 < 3.1.83.1.8
microsoftmicrosoft.aspnetcore.app.runtime.linux-x64>= 3.1.0 < 3.1.83.1.8
microsoftmicrosoft.aspnetcore.app.runtime.osx-x64>= 3.1.0 < 3.1.83.1.8
microsoftmicrosoft.aspnetcore.app.runtime.win-arm>= 3.1.0 < 3.1.83.1.8
microsoftmicrosoft.aspnetcore.app.runtime.win-arm64>= 3.1.5 < 3.1.83.1.8
microsoftmicrosoft.aspnetcore.app.runtime.win-x64>= 3.1.0 < 3.1.83.1.8
microsoftmicrosoft.aspnetcore.app.runtime.win-x86>= 3.1.0 < 3.1.83.1.8
msrcasp.net_core_2.1
msrcasp.net_core_3.1
redhatenterprise_linux
redhatenterprise_linux_aus
redhatenterprise_linux_aus
redhatenterprise_linux_aus
redhatenterprise_linux_eus
redhatenterprise_linux_eus
redhatenterprise_linux_eus

CVSS provenance

nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:N/I:P/A:N
vendor_msrc7.5HIGH
vendor_redhat7.5HIGH
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