Vulnerability · CVE-2026-70159
Microsoft Security Advisory CVE-2026-70159 - ASP.NET Core Denial of Service Vulnerability
Published Oct 13, 2026 · Microsoft Security Advisory -
Check if you run it
No confirmed exploitation is on record for CVE-2026-70159. EPSS is 1.06%. Act only if a listed version of Microsoft Security Advisory - is installed.
Gaps on this record
- The stored product name is a package slug. The name on this page is taken from the title (Microsoft Security Advisory -).
- No version range is stored. A customer cannot check an installed version against this record.
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- Severity
- Unknown—
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 1.06%
- Remediation
- Not established
- Affected products
- nuget microsoft.aspnetcore.signalr.common · nuget microsoft.aspnetcore.signalr.core
Microsoft is releasing this security advisory to provide information about a vulnerability in Microsoft.AspNetCore.SignalR.Common and Microsoft.AspNetCore.SignalR.Core. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability. SignalR stateful reconnect clients can indefinitely block broadcasts through MessageBuffer.ResendAsync backpressure and retain associated resources.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- nuget microsoft.aspnetcore.signalr.commonversion unspecified
- nuget microsoft.aspnetcore.signalr.coreversion unspecified
How to fix CVE-2026-70159
Recommended remediation
No required-action text, fix commit, or clear fixed-version range is stored yet.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2026-70159. EPSS is 1.06%. Act only if a listed version of Microsoft Security Advisory - is installed.
Which versions are affected?
Affected version ranges are not on this record. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
No weakness class is stored. EPSS 1.06%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
Timeline
Detection, updates, and resolution for this record.
Oct 13, 2026 · GitLab Advisory Database
Detected
Microsoft is releasing this security advisory to provide information about a vulnerability in Microsoft.AspNetCore.SignalR.Common and Microsoft.AspNetCore.SignalR.Core. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability. SignalR stateful reconnect clients can indefinitely block broadcasts through MessageBuffer.ResendAsync backpr
Sources
- CVE.orgVulnerability recordCVE-2026-70159
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2026-70159
30-day exploitation probability 1.1%
first.org - GitLab Advisory DatabasePackage advisoryCVE-2026-70159
Microsoft is releasing this security advisory to provide information about a vulnerability in Microsoft.AspNetCore.SignalR.Common and Microsoft.AspNetCore.SignalR.Core. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability. SignalR stateful reconnect clients can indefinitely block broadcasts through MessageBuffer.ResendAsync backpr
advisories.gitlab.com
Freshness
Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.