CVE-2020-1045
<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…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (5.93%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
- EPSS
- 5.93% probability · 93th percentile
- CISA KEV
- Not listed
- Affected
- microsoft/asp.net core · fedoraproject/fedora · redhat/enterprise linux · redhat/enterprise linux aus · redhat/enterprise linux eus · redhat/enterprise linux tus
- Source
- secure@microsoft.com
References
- https://access.redhat.com/errata/RHSA-2020:3699Third Party Advisory
- https://github.com/dotnet/core/blob/main/release-notes/3.1/3.1.8/3.1.8.md#changes-in-318Release Notes, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5LN2FUVBSVPGK7AU3NMLO3YR6CGONQPB/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ASICXQXS4M7MTAF6SGQMCLCA63DLCUT3/
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-1045Patch, Vendor Advisory
- https://security.snyk.io/vuln/SNYK-RHEL8-DOTNET-1439600Third Party Advisory
- https://access.redhat.com/errata/RHSA-2020:3699Third Party Advisory
- https://github.com/dotnet/core/blob/main/release-notes/3.1/3.1.8/3.1.8.md#changes-in-318Release Notes, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5LN2FUVBSVPGK7AU3NMLO3YR6CGONQPB/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ASICXQXS4M7MTAF6SGQMCLCA63DLCUT3/
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-1045Patch, Vendor Advisory
- https://security.snyk.io/vuln/SNYK-RHEL8-DOTNET-1439600Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.