Mattermost up to 9.11.5/10.0.3/10.1.3 post.props.attachments type conversion

CVSS Meta Temp Score
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CTI Interest Score
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5.7$0-$5k0.00

Summaryinfo

A vulnerability has been found in Mattermost up to 9.11.5/10.0.3/10.1.3 and classified as problematic. The affected element is the function post.props.attachments. The manipulation leads to type conversion. This vulnerability is documented as CVE-2025-21088. The attack can be initiated remotely. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Mattermost up to 9.11.5/10.0.3/10.1.3 and classified as problematic. This issue affects the function post.props.attachments. The manipulation with an unknown input leads to a type conversion vulnerability. Using CWE to declare the problem leads to CWE-704. The product does not correctly convert an object, resource, or structure from one type to a different type. Impacted is availability. The summary by CVE is:

Mattermost versions 10.2.x <= 10.2.0, 9.11.x <= 9.11.5, 10.0.x <= 10.0.3, 10.1.x <= 10.1.3 fail to properly validate the style of proto supplied to an action's style in post.props.attachments, which allows an attacker to crash the frontend via crafted malicious input.

The weakness was released by C0rydoras. The advisory is shared at mattermost.com. The identification of this vulnerability is CVE-2025-21088 since 01/15/2025. The exploitation is known to be easy. The attack may be initiated remotely. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 214906 (SUSE SLES15 / openSUSE 15 Security Update : govulncheck-vulndb (SUSE-SU-2025:0297-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 9.11.6, 10.0.4, 10.1.4, 10.2.1 or 10.3.0 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (214906). 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: 5.8
VulDB Meta Temp Score: 5.7

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

NVD Base Score: 6.5
NVD Vector: 🔍

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: Type conversion
CWE: CWE-704
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: 214906
Nessus Name: SUSE SLES15 / openSUSE 15 Security Update : govulncheck-vulndb (SUSE-SU-2025:0297-1)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Mattermost 9.11.6/10.0.4/10.1.4/10.2.1/10.3.0

Timelineinfo

01/15/2025 🔍
01/15/2025 +0 days 🔍
01/15/2025 +0 days 🔍
10/01/2025 +258 days 🔍

Sourcesinfo

Advisory: mattermost.com
Researcher: C0rydoras
Status: Confirmed

CVE: CVE-2025-21088 (🔍)
GCVE (CVE): GCVE-0-2025-21088
GCVE (VulDB): GCVE-100-292001

Entryinfo

Created: 01/15/2025 18:08
Updated: 10/01/2025 00:20
Changes: 01/15/2025 18:08 (64), 02/04/2025 07:07 (2), 10/01/2025 00:20 (12)
Complete: 🔍
Cache ID: 216::103

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

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