Microsoft Skype for Business Server 2015 CU13/2019 CU8/Subscription Edition CU1 file inclusion

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.6$5k-$25k0.00

Summaryinfo

A vulnerability was found in Microsoft Skype for Business Server 2015 CU13/2019 CU8/Subscription Edition CU1 and classified as very critical. Affected by this issue is some unknown functionality. The manipulation results in file inclusion. This vulnerability is identified as CVE-2026-66302. The attack can be executed remotely. There is not any exploit available. It is advisable to implement a patch to correct this issue.

Detailsinfo

A vulnerability was found in Microsoft Skype for Business Server 2015 CU13/2019 CU8/Subscription Edition CU1. It has been classified as very critical. Affected is an unknown code. The manipulation with an unknown input leads to a file inclusion vulnerability. CWE is classifying the issue as CWE-73. The product allows user input to control or influence paths or file names that are used in filesystem operations. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

External control of file name or path in Skype for Business 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-2026-66302 since 07/24/2026. 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 $5k-$25k (estimation calculated on 09/12/2026).

The vulnerability scanner Nessus provides a plugin with the ID 344822 (Skype for Business (September 2026)), which helps to determine the existence of the flaw in a target environment.

Applying a patch is able to eliminate this problem.

The vulnerability is also documented in the vulnerability database at Tenable (344822). 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: File inclusion
CWE: CWE-73
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 344822
Nessus Name: Skype for Business (September 2026)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Timelineinfo

07/24/2026 CVE reserved
09/08/2026 +46 days Advisory disclosed
09/08/2026 +0 days VulDB entry created
09/12/2026 +4 days VulDB entry last update

Sourcesinfo

Vendor: microsoft.com

Advisory: msrc.microsoft.com
Status: Confirmed

CNA: microsoft
CVE: CVE-2026-66302 (🔒)

GCVE (CVE): GCVE-0-2026-66302
GCVE (VulDB): GCVE-100-400236
scip Labs: https://www.scip.ch/en/?labs.20140918

Entryinfo

Created: 09/08/2026 21:11
Updated: 09/12/2026 04:09
Changes: 09/08/2026 21:11 (62), 09/12/2026 04:09 (2)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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