Mattermost up to 10.11.7/10.12.3/11.0.5/11.1.0 incorrect implementation of authentication algorithm

CVSS Meta Temp Score
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CTI Interest Score
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7.2$0-$5k0.00

Summaryinfo

A vulnerability has been found in Mattermost up to 10.11.7/10.12.3/11.0.5/11.1.0 and classified as critical. The affected element is an unknown function. The manipulation leads to incorrect implementation of authentication algorithm. This vulnerability is traded as CVE-2025-14273. It is possible to initiate the attack remotely. There is no exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Mattermost up to 10.11.7/10.12.3/11.0.5/11.1.0 and classified as critical. This issue affects an unknown part. The manipulation with an unknown input leads to a incorrect implementation of authentication algorithm vulnerability. Using CWE to declare the problem leads to CWE-303. The requirements for the product dictate the use of an established authentication algorithm, but the implementation of the algorithm is incorrect. Impacted is integrity, and availability. The summary by CVE is:

Mattermost versions 11.1.x <= 11.1.0, 11.0.x <= 11.0.5, 10.12.x <= 10.12.3, 10.11.x <= 10.11.7 with the Jira plugin enabled and Mattermost Jira plugin versions <=4.4.0 fail to enforce authentication and issue-key path restrictions in the Jira plugin, which allows an unauthenticated attacker who knows a valid user ID to issue authenticated GET and POST requests to the Jira server via crafted plugin payloads that spoof the user ID and inject arbitrary issue key paths. Mattermost Advisory ID: MMSA-2025-00555

The weakness was shared by Juho Forsén. It is possible to read the advisory at mattermost.com. The identification of this vulnerability is CVE-2025-14273 since 12/08/2025. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. The technical details are unknown and an exploit is not publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 280123 (Mattermost Server 10.11.x < 10.11.8 / 10.12.x < 10.12.4 / 11.0.x <= 11.0.6 / 11.1.x <= 11.1.1 Improper Authentication (MMSA-2025-00555)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 10.11.8, 10.12.4, 11.0.6, 11.1.1 or 11.2.0 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (280123), EUVD (EUVD-2025-204707) and CERT Bund (WID-SEC-2025-2913). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

  • Mattermost Mattermost

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.2

VulDB Base Score: 6.5
VulDB Temp Score: 6.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 8.3
NVD Vector: 🔒

CNA Base Score: 7.2
CNA Vector (Mattermost): 🔒

CVSSv2info

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

Exploitinginfo

Class: Incorrect implementation of authentication algorithm
CWE: CWE-303
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: 280123
Nessus Name: Mattermost Server 10.11.x < 10.11.8 / 10.12.x < 10.12.4 / 11.0.x <= 11.0.6 / 11.1.x <= 11.1.1 Improper Authentication (MMSA-2025-00555)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Mattermost 10.11.8/10.12.4/11.0.6/11.1.1/11.2.0

Timelineinfo

12/08/2025 CVE reserved
12/22/2025 +14 days Advisory disclosed
12/22/2025 +0 days VulDB entry created
12/30/2025 +8 days VulDB entry last update

Sourcesinfo

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

CVE: CVE-2025-14273 (🔒)
GCVE (CVE): GCVE-0-2025-14273
GCVE (VulDB): GCVE-100-337739
EUVD: 🔒
CERT Bund: WID-SEC-2025-2913 - Mattermost: Schwachstelle erm&ouml;glicht Umgehen von Sicherheitsvorkehrungen

Entryinfo

Created: 12/22/2025 14:02
Updated: 12/30/2025 05:31
Changes: 12/22/2025 14:02 (63), 12/22/2025 18:49 (1), 12/23/2025 11:34 (7), 12/29/2025 21:08 (11), 12/30/2025 05:31 (2)
Complete: 🔍
Cache ID: 216::103

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

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