CERT-FR Flags 21 Flaws in .NET
CERT-FR advises multiple .NET versions (8.0–11.0) contain vulnerabilities enabling remote code execution, privilege escalation, and denial of service; patches available.
Sourcecert.cyber.gouv.fr — open the original
What to check
- Applies to
- The 22 CVEs named below. Whether you run an affected version is not assessed: check the versions the source lists.
- Exploitation
- No exploitation in the wild and no public exploit is recorded for the CVEs named.
CERT-FR issued an advisory covering 21 CVEs affecting Microsoft .NET versions 8.0, 9.0, 10.0, and 11.0 across Linux, macOS, and Windows platforms. The vulnerabilities collectively allow attackers to compromise data confidentiality, bypass security policies, cause remote denial of service, execute arbitrary code remotely, and escalate privileges. No evidence of active exploitation in the wild is mentioned in the bulletin.
Affected systems include .NET 8.0 prior to 8.0.34 (Linux/macOS) or 8.0.428 (Windows), .NET 9.0 prior to 9.0.23 (Linux/macOS) or 9.0.321 (Windows), .NET 10.0 prior to 10.0.404 across all platforms, and .NET 11.0 prior to 11.0.100 across all platforms. CERT-FR directs administrators to Microsoft's security bulletins for patch details and recommends applying updates to the fixed versions listed.
This is a routine vendor patch advisory compiled by a national CERT, aggregating Microsoft's own disclosures rather than original research. Defenders running any of the affected .NET runtime versions should prioritize patching per standard vulnerability management processes, particularly given the range of impacts including remote code execution.
Mentioned in this report
Source reporting: https://www.cert.cyber.gouv.fr/avis/CERTFR-2026-AVI-1512
Free public brief. Slack alerts on the vendors you run come with the paid plans, and a new account gets three days of them, no card.
What this brief leaves out
This page is the free tier: the write-up, the severity, the names. In the app the same report carries live profiles of the CVEs it names. The paid plans add the security research and news reporting the free tier leaves out.
It sits in a corpus of 16,436 reports from 149 sources, 661 of them written in the last seven days, and it grows through the day.
A new account starts with three days of all of it, no card, then keeps the government and CERT reporting free. Slack alerts are a paid-plan feature: name the vendors you run and Slack hears about the reports that touch them, not the rest of the week's. Nothing is charged unless you subscribe.
Create a free account What it costs