Input validation error in ASP.NET Core MVC - CVE-2020-1045
Published: September 8, 2020
Vulnerability identifier: #VU46500
CSH Severity: Medium
CVSS v4: 6.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2020-1045
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to bypass certain security restrictions.
The vulnerability exists due to insufficient validation of 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.
Affected software
ASP.NET Core MVC
rh-dotnet31-dotnet (Red Hat package)
dotnet3.1 (Red Hat package)
dotnet3.1
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux Server - TUS
Fedora
rh-dotnet31-dotnet (Red Hat package)
dotnet3.1 (Red Hat package)
dotnet3.1
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux Server - TUS
Fedora
How to mitigate CVE-2020-1045
Install updates from vendor's website.
rh-dotnet31-dotnet (Red Hat package) - update to 3.1.108-1.el7
dotnet3.1 (Red Hat package) - update to 3.1.108-2.el8_2
dotnet3.1 - addressed in versions 3.1.108-1.fc32, 3.1.108-1.fc33
dotnet3.1 (Red Hat package) - update to 3.1.108-2.el8_2
dotnet3.1 - addressed in versions 3.1.108-1.fc32, 3.1.108-1.fc33