CVE-2026-35433
published 2026-05-12CVE-2026-35433: Improper input validation in .NET allows an unauthorized attacker to elevate privileges locally.
PriorityP343high7.3CVSS 3.1
AVLACLPRNUIRSUCHIHAL
EPSS
0.66%
47.5th percentile
Improper input validation in .NET allows an unauthorized attacker to elevate privileges locally.
Affected
15 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| microsoft | microsoft_net_framework_3.5 | >= 3.5.0 < 4.8.9334.0 and 4.8.4802.0 | 4.8.9334.0 and 4.8.4802.0 |
| microsoft | microsoft_net_framework_3.5_and_4.7.2 | >= 4.7.0 < 4.8.9334.0 and 4.8.4802.0 | 4.8.9334.0 and 4.8.4802.0 |
| microsoft | microsoft_net_framework_3.5_and_4.8 | >= 4.8.0 < 4.8.9334.0 and 4.8.4802.0 | 4.8.9334.0 and 4.8.4802.0 |
| microsoft | microsoft_net_framework_3.5_and_4.8.1 | >= 4.8.1 < 4.8.9334.0 and 4.8.4802.0 | 4.8.9334.0 and 4.8.4802.0 |
| microsoft | microsoft_net_framework_4.8 | >= 4.8.0 < 4.8.9334.0 and 4.8.4802.0 | 4.8.9334.0 and 4.8.4802.0 |
| microsoft | net | >= 10.0.0 < 10.0.8 | 10.0.8 |
| microsoft | net | >= 8.0.0 < 8.0.27 | 8.0.27 |
| microsoft | net | >= 9.0.0 < 9.0.16 | 9.0.16 |
| microsoft | net_10.0 | >= 10.0.0 < 10.0.8 | 10.0.8 |
| microsoft | net_8.0 | >= 8.0.0 < 8.0.27 | 8.0.27 |
| microsoft | net_9.0 | >= 9.0.0 < 9.0.16 | 9.0.16 |
| microsoft | net_framework | — | — |
| microsoft | net_framework | — | — |
| microsoft | net_framework | — | — |
| microsoft | net_framework | — | — |
CVSS provenance
nvdv3.17.3HIGHCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L
ghsa7.3HIGH
vendor_redhat7.3HIGH
Stop checking back — get the weekly exploitation signal.
Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.
GHSA
Microsoft Security Advisory CVE-2026-35433 – .NET Elevation of Privilege Vulnerability
ghsa·2026-05-18·CVSS 7.3
CVE-2026-35433 [HIGH] CWE-122 Microsoft Security Advisory CVE-2026-35433 – .NET Elevation of Privilege Vulnerability
Microsoft Security Advisory CVE-2026-35433 – .NET Elevation of Privilege Vulnerability
## Executive Summary:
Microsoft is releasing this security advisory to provide information about a vulnerability in .NET 8.0, .NET 9.0, and .NET 10.0. This advisory also provides guidance on what developers can do to update their applications to remove this vulnerability.
Improper input validation in .NET allows an unauthorized attacker to elevate privileges locally.
## Announcement
Announcement for this issue can be found at https://github.com/dotnet/announcements/issues/398
## CVSS Details
- **Version:** 3.1
- **Severity:** High
- **Score:** 7.3
- **Vector:** AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L/E:U/RL:O/RC:C
- **Weakness:** CWE-122: Heap-based Buffer Overflow, CWE-20: Improper Input Validation
Red Hat
dotnet: .NET: improper input validation allows an attacker to elevate privileges locally
vendor_redhat·2026-05-12·CVSS 7.3
CVE-2026-35433 [HIGH] CWE-20 dotnet: .NET: improper input validation allows an attacker to elevate privileges locally
dotnet: .NET: improper input validation allows an attacker to elevate privileges locally
Improper input validation in .NET allows an unauthorized attacker to elevate privileges locally.
A flaw was found in dotnet. Improper input validation and an integer overflow in .NET allow an unauthenticated attacker to elevate privileges locally.
Statement: As this flaw allows an unauthenticated attacker to elevate privileges locally, it has been rated with an important severity.
Mitigation: Red Hat has investigated whether a possible mitigation exists for this issue, and has not been able to identify a practical example. Please update the affected package as soon as possible.
Package: dotnet10.0 (Red Hat Enterprise Linux 10) - Under investigation
Package: dotnet8.0 (Red Hat Enterprise Linux 10)
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-35433 dotnet: .NET: improper input validation allows an attacker to elevate privileges locally
bugzilla·2026-05-12·CVSS 7.3
CVE-2026-35433 [HIGH] CVE-2026-35433 dotnet: .NET: improper input validation allows an attacker to elevate privileges locally
CVE-2026-35433 dotnet: .NET: improper input validation allows an attacker to elevate privileges locally
Improper input validation in .NET allows an unauthorized attacker to elevate privileges locally.
Rapid7
Patch Tuesday - May 2026
blogs_rapid7·2026-05-13·CVSS 10.0
CVE-2026-41089 [CRITICAL] Patch Tuesday - May 2026
Microsoft is publishing 137 vulnerabilities on May 2026 Patch Tuesday . Microsoft is not aware of exploitation in the wild or public disclosure for any of these vulnerabilities. So far this month, Microsoft has provided patches to address 133 browser vulnerabilities, which are not included in the Patch Tuesday count above.
## Windows Netlogon: critical RCE
Anyone responsible for securing a domain controller should prioritize remediation of CVE-2026-41089 , which is a critical stack-based buffer overflow in Windows Netlogon with a CVSS v3 base score of 9.8. Exploitation leads to execution in the context of the Netlogon service, so that’s SYSTEM privileges on the domain controller. For most pentesters, that’s the point at which the customer report more or less writes itself. No privileges
Sans Isc
Microsoft May 2026 Patch Tuesday, (Tue, May 12th)
blogs_sans_isc·2026-05-12·CVSS 4.3
CVE-2026-41103 [MEDIUM] Microsoft May 2026 Patch Tuesday, (Tue, May 12th)
Microsoft May 2026 Patch Tuesday
Published: 2026-05-12. Last Updated: 2026-05-12 18:29:36 UTC
by Johannes Ullrich (Version: 1)
0 comment(s)
Today's Microsoft patch Tuesday fixes 137 different vulnerabilities. In addition, the update addresses 137 Chromium-related issues affecting Microsoft Edge.
There are no already disclosed or already exploited vulnerabilities included in today's patches. I removed the Chromium issues from the table below and included only the 137 Microsoft issues to make it more readable.
Note that issues related to Microsoft Azure are labeled as "no customer action required.
Significant Vulnerabilities of interest:
CVE-2026-41103: This vulnerability affects the Microsoft SSO Plugin for Jira & Confluence. Exploitation could lead to an elevation of privileges. Wit
2026-05-12
Published