Mattermost up to 10.5.1 MS Teams Plugin timing discrepancy

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.7$0-$5k0.00

Summaryinfo

A vulnerability marked as problematic has been reported in Mattermost up to 10.5.1. This issue affects some unknown processing of the component MS Teams Plugin. Performing a manipulation results in timing discrepancy. This vulnerability is identified as CVE-2025-27936. The attack can be initiated remotely. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in Mattermost up to 10.5.1. This affects an unknown code of the component MS Teams Plugin. The manipulation with an unknown input leads to a timing discrepancy vulnerability. CWE is classifying the issue as CWE-208. Two separate operations in a product require different amounts of time to complete, in a way that is observable to an actor and reveals security-relevant information about the state of the product, such as whether a particular operation was successful or not. This is going to have an impact on confidentiality. The summary by CVE is:

Mattermost Plugin MSTeams versions <2.1.0 and Mattermost Server versions 10.5.x <=10.5.1 with the MS Teams plugin enabled fail to perform constant time comparison on a MSTeams plugin webhook secret which allows an attacker to retrieve the webhook secret of the MSTeams plugin via a timing attack during webhook secret comparison.

The weakness was released by Juho Forsén. The advisory is shared at mattermost.com. This vulnerability is uniquely identified as CVE-2025-27936 since 04/08/2025. The exploitability is told to be difficult. It is possible to initiate the attack remotely. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1592 for this issue.

Upgrading to version 10.5.2 or 10.6.0 eliminates this vulnerability.

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

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.8
VulDB Meta Temp Score: 4.7

VulDB Base Score: 3.1
VulDB Temp Score: 3.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.9
NVD Vector: 🔍

CNA Base Score: 5.3
CNA Vector (Mattermost): 🔍

CVSSv2info

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

Exploitinginfo

Class: Timing discrepancy
CWE: CWE-208 / CWE-203 / CWE-200
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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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Mattermost 10.5.2/10.6.0

Timelineinfo

04/08/2025 🔍
04/16/2025 +8 days 🔍
04/16/2025 +0 days 🔍
01/14/2026 +273 days 🔍

Sourcesinfo

Advisory: mattermost.com
Researcher: Juho Forsén
Status: Confirmed

CVE: CVE-2025-27936 (🔍)
GCVE (CVE): GCVE-0-2025-27936
GCVE (VulDB): GCVE-100-305001

Entryinfo

Created: 04/16/2025 14:12
Updated: 01/14/2026 19:27
Changes: 04/16/2025 14:12 (64), 01/14/2026 19:27 (12)
Complete: 🔍
Cache ID: 216::103

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

Discussion

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