Mattermost up to 11.7.10/11.8.5/11.9.1/11.10.1 PDF denial of service

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-$5k0.61

Summaryinfo

A vulnerability identified as problematic has been detected in Mattermost up to 11.7.10/11.8.5/11.9.1/11.10.1. Affected is an unknown function of the component PDF Handler. The manipulation leads to denial of service. This vulnerability is documented as CVE-2026-93850. The attack can be initiated remotely. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Mattermost up to 11.7.10/11.8.5/11.9.1/11.10.1. It has been rated as problematic. This issue affects some unknown functionality of the component PDF Handler. The manipulation with an unknown input leads to a denial of service vulnerability. Using CWE to declare the problem leads to CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. Impacted is availability. The summary by CVE is:

Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10, 11.10.x <= 11.10.1 fail to bind the volume of text extracted from an uploaded PDF which allows an authenticated user to exhaust server memory and cause a denial of service via a crafted PDF whose compressed content stream expands into a very large amount of text.. Mattermost Advisory ID: MMSA-2026-00769

It is possible to read the advisory at mattermost.com. The identification of this vulnerability is CVE-2026-93850 since 09/18/2026. The exploitation is known to be easy. The attack may be initiated remotely. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1499 according to MITRE ATT&CK.

Upgrading to version 11.7.11, 11.8.6, 11.9.2, 11.10.2 or 11.11.0 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

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 (Mattermost): 🔒

CVSSv2info

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

Exploitinginfo

Class: Denial of service
CWE: CWE-404
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: Mattermost 11.7.11/11.8.6/11.9.2/11.10.2/11.11.0

Timelineinfo

09/18/2026 CVE reserved
10/26/2026 +38 days Advisory disclosed
10/26/2026 +0 days VulDB entry created
10/26/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: mattermost.com
Status: Confirmed

CVE: CVE-2026-93850 (🔒)
GCVE (CVE): GCVE-0-2026-93850
GCVE (VulDB): GCVE-100-426491

Entryinfo

Created: 10/26/2026 16:27
Changes: 10/26/2026 16:27 (63)
Complete: 🔍
Cache ID: 216::103

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