Kiteworks Email Protection Gateway up to 9.5.0 Large File Exchange Feature improper authorization

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.3$0-$5k0.39

Summaryinfo

A vulnerability, which was classified as problematic, has been found in Kiteworks Email Protection Gateway up to 9.5.0. The impacted element is an unknown function of the component Large File Exchange Feature. This manipulation causes improper authorization. This vulnerability is handled as CVE-2026-102139. The attack can be initiated remotely. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in Kiteworks Email Protection Gateway up to 9.5.0. It has been declared as problematic. Affected by this vulnerability is an unknown functionality of the component Large File Exchange Feature. The manipulation with an unknown input leads to a improper authorization vulnerability. The CWE definition for the vulnerability is CWE-285. The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. As an impact it is known to affect confidentiality. The summary by CVE is:

An authorization check in the large file exchange feature of Kiteworks Email Protection Gateway did not correctly establish that the requesting user was a party to the package being requested. An authenticated user of that optional feature could read the subject, message body, and attachments of packages they neither sent nor received.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-102139 since 09/28/2026. The exploitation appears to be easy. The attack can be launched remotely. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1548.002 for this issue.

Upgrading to version 9.5.1 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.5
CNA Vector (cisa-cg): 🔒

CVSSv2info

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

Exploitinginfo

Class: Improper authorization
CWE: CWE-285 / CWE-266
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: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Email Protection Gateway 9.5.1

Timelineinfo

09/28/2026 CVE reserved
09/30/2026 +2 days Advisory disclosed
09/30/2026 +0 days VulDB entry created
09/30/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-102139 (🔒)
GCVE (CVE): GCVE-0-2026-102139
GCVE (VulDB): GCVE-100-412441

Entryinfo

Created: 09/30/2026 23:38
Changes: 09/30/2026 23:38 (64)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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