Microsoft Windows Server 2012 up to Server 2022 ONCRPC XDR Driver use after free

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
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CTI Interest Score
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9.6$25k-$100k0.00+

Summaryinfo

A vulnerability, which was classified as very critical, was found in Microsoft Windows Server 2012 up to Server 2022. Affected is an unknown function of the component ONCRPC XDR Driver. The manipulation results in use after free. This vulnerability is cataloged as CVE-2026-78445. The attack may be launched remotely. There is no exploit available. It is advisable to implement a patch to correct this issue.

Detailsinfo

A vulnerability classified as very critical has been found in Microsoft Windows Server 2012 up to Server 2022. Affected is some unknown functionality of the component ONCRPC XDR Driver. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

Use after free in Windows Services for NFS ONCRPC XDR Driver allows an unauthorized attacker to execute code over a network.

The advisory is shared for download at msrc.microsoft.com. This vulnerability is traded as CVE-2026-78445 since 08/24/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $25k-$100k (estimation calculated on 09/09/2026).

Applying a patch is able to eliminate this problem.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.9
VulDB Meta Temp Score: 9.6

VulDB Base Score: 10.0
VulDB Temp Score: 9.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 9.8
CNA Vector (microsoft): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Timelineinfo

08/24/2026 CVE reserved
09/09/2026 +16 days Advisory disclosed
09/09/2026 +0 days VulDB entry created
09/09/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

Advisory: msrc.microsoft.com
Status: Confirmed

CVE: CVE-2026-78445 (🔒)
GCVE (CVE): GCVE-0-2026-78445
GCVE (VulDB): GCVE-100-401004

Entryinfo

Created: 09/09/2026 02:30
Changes: 09/09/2026 02:30 (63)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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