Vulnerability · Published Oct 13, 2026 · Assigned by microsoft

CVE-2026-97801.NET Framework Tampering Vulnerability

High 7.5

In plain English

A high-severity security flaw in Microsoft .NET Framework 3.5 from Microsoft. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 55% of all known vulnerabilities).

Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.7%top 45.4% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

Improper validation of specified type of input in .NET Framework allows an unauthorized attacker to perform tampering over a network.

Affected products (as reported)

VendorProductVersions
Microsoft Microsoft .NET Framework 3.5 3.5.0 – before 2.0.50727.9188 AND 3.0.30729.9171
Microsoft Microsoft .NET Framework 3.5 AND 4.6.2/4.7/4.7.1/4.7.2 3.0.0.0 – before 2.0.50727.8987 AND 3.0.30729.8982 AND 4.7.4150.0
Microsoft Microsoft .NET Framework 3.5 AND 4.7.2 4.7.0 – before 2.0.50727.9073 AND 3.0.30729.9070 AND 4.7.4150.0
Microsoft Microsoft .NET Framework 3.5 AND 4.8 4.8.0 – before 2.0.50727.9073 AND 3.0.30729.9070 AND 4.8.4811.0
Microsoft Microsoft .NET Framework 3.5 AND 4.8.1 4.8.1 – before 2.0.50727.9188 AND 3.0.30729.9171 AND 4.8.9363.0
Microsoft Microsoft .NET Framework 4.6.2/4.7/4.7.1/4.7.2 4.7.0 – before 4.7.4150.0
Microsoft Microsoft .NET Framework 4.8 4.8.0 – before 4.8.4811.0
Microsoft Microsoft .NET Framework 4.8.1 4.8.0.0 – before 4.8.9363.0

Weakness: CWE-1287 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N/E:U/RL:O/RC:C

References