CVE-2026-97801: .NET Framework Tampering Vulnerability

High severity · published Oct 13, 2026

CVE-2026-97801

.NET Framework Tampering Vulnerability

7.5

CVSS

0.7%

EPSS

On KEV

Description

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

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Attack vector

Network

Complexity

Low

Privileges

None

User interaction

None

Confidentiality

None

Integrity

High

Availability

None

Scope

Unchanged

Exploitation

Is it being used?

Exploit prediction (EPSS)0.7% · higher than 54% of CVEs

Exploited in the wildNo evidence yet

CISA KEVNot listed

Ransomware campaign useNot known

Affected products

Which versions

Microsoft .NET Framework 3.5 · Microsoft

3.5.0 before 2.0.50727.9188 AND 3.0.30729.9171 · source: vendor

Microsoft .NET Framework 3.5 AND 4.6.2/4.7/4.7.1/4.7.2 · Microsoft

3.0.0.0 before 2.0.50727.8987 AND 3.0.30729.8982 AND 4.7.4150.0 · source: vendor

Microsoft .NET Framework 3.5 AND 4.7.2 · Microsoft

4.7.0 before 2.0.50727.9073 AND 3.0.30729.9070 AND 4.7.4150.0 · source: vendor

Microsoft .NET Framework 3.5 AND 4.8 · Microsoft

4.8.0 before 2.0.50727.9073 AND 3.0.30729.9070 AND 4.8.4811.0 · source: vendor

Microsoft .NET Framework 3.5 AND 4.8.1 · Microsoft

4.8.1 before 2.0.50727.9188 AND 3.0.30729.9171 AND 4.8.9363.0 · source: vendor

Microsoft .NET Framework 4.6.2/4.7/4.7.1/4.7.2 · Microsoft

4.7.0 before 4.7.4150.0 · source: vendor

Microsoft .NET Framework 4.8 · Microsoft

4.8.0 before 4.8.4811.0 · source: vendor

Microsoft .NET Framework 4.8.1 · Microsoft

4.8.0.0 before 4.8.9363.0 · source: vendor

Affected product

Microsoft .NET Framework 3.5

Microsoft

All Microsoft .NET Framework 3.5 CVEs

References

NVD

https://nvd.nist.gov/vuln/detail/CVE-2026-97801

CVE.org

https://www.cve.org/CVERecord?id=CVE-2026-97801

vendor-advisory

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-97801