CVE-2026-25667
High
Description
ASP.NET Core Kestrel in Microsoft .NET 8.0 before 8.0.22 and .NET 9.0 before 9.0.11 allows a remote attacker to cause excessive CPU consumption by sending a crafted QUIC packet, because of an incorrect exit condition for HTTP/3 Encoder/Decoder stream processing.
SeverityHigh
CVSS7.5
Exploit probability—
Product
Microsoft .net
PublishedMar 19, 2026
First seenMar 19, 2026
Weakness typeCWE-400Uncontrolled resource consumption
How to fix
Update
- microsoft .net8.0.22, 9.0.11 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| microsoft .net | 8.0.0 ≤ v < 8.0.22, 9.0.0 ≤ v < 9.0.11 | 8.0.22, 9.0.11 |
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