Red Hat Security Advisory: .NET 9.0 security update
Affects Red Hat .NET 9.0Source GCVE Database
Not known to be exploited · CVSS 7.5 High · fixed in Red Hat package updates : patch Red Hat microsoft.net soon.
Data as of 6 Nov 2026, 02:06 UTC
- Patch
- Available – fixed in 10.0.8, 8.0.27, 9.0.16
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:CExploitation evidence
Disclosed: evidence found.
CVE published 12 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 5 Nov 2026.
What to do
Upgrade .NET to 10.0.8 (10.0) or 8.0.27 (8.0) or 9.0.16 (9.0).
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Microsoft.NET 10.0 | Affected
| Fixed in
|
| Microsoft.NET 8.0 | Affected
| Fixed in
|
| Microsoft.NET 9.0 | Affected
| Fixed in
|
NuGetmicrosoft.netpkg:nuget/microsoft.netOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Red Hat has released fixed versions: .NET SDK 9.0.117 and .NET Runtime 9.0.16. Users should update to these versions as soon as possible. Detailed update instructions are available from Red Hat's advisory. Since official fixes are available, applying these updates fully mitigates the vulnerability.
Description
.NET 9.0 contained a security vulnerability that could cause an infinite loop, allowing an attacker to cause a denial of service. Red Hat has released updated versions of the .NET SDK (9.0.117) and .NET Runtime (9.0.16) that address this issue. The vulnerability is identified as CVE-2026-42899 and is rated with a high severity impact by Red Hat. This affects Red Hat Enterprise Linux 9.6 Extended Update Support and related products. Users are advised to apply the provided updates to remediate the vulnerability.