Mattermost up to 10.11.10/11.3.x Private Channel operation after expiration

CVSS Meta Temp Score
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CTI Interest Score
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4.2$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, has been found in Mattermost up to 10.11.10/11.3.x. This affects an unknown part of the component Private Channel Handler. This manipulation causes operation after expiration. This vulnerability is handled as CVE-2026-1629. 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 Mattermost up to 10.11.10/11.3.x. It has been declared as problematic. Affected by this vulnerability is an unknown functionality of the component Private Channel Handler. The manipulation with an unknown input leads to a operation after expiration vulnerability. The CWE definition for the vulnerability is CWE-672. The product uses, accesses, or otherwise operates on a resource after that resource has been expired, released, or revoked. As an impact it is known to affect confidentiality. The summary by CVE is:

Mattermost versions 10.11.x <= 10.11.10 Fail to invalidate cached permalink preview data when a user loses channel access which allows the user to continue viewing private channel content via previously cached permalink previews until cache reset or relogin.. Mattermost Advisory ID: MMSA-2026-00580

The weakness was released by Joshua Rogers (Permalink). It is possible to read the advisory at mattermost.com. This vulnerability is known as CVE-2026-1629 since 01/29/2026. The exploitation appears to be easy. The attack can be launched remotely. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 10.11.11 or 11.4.0 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-12516). 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: 4.3
VulDB Meta Temp Score: 4.2

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

CNA Base Score: 4.3
CNA Vector (Mattermost): 🔒

CVSSv2info

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

Exploitinginfo

Class: Operation after expiration
CWE: CWE-672
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 10.11.11/11.4.0

Timelineinfo

01/29/2026 CVE reserved
03/16/2026 +46 days Advisory disclosed
03/16/2026 +0 days VulDB entry created
03/21/2026 +5 days VulDB entry last update

Sourcesinfo

Advisory: mattermost.com
Researcher: Joshua Rogers (Permalink)
Status: Confirmed

CVE: CVE-2026-1629 (🔒)
GCVE (CVE): GCVE-0-2026-1629
GCVE (VulDB): GCVE-100-351331
EUVD: 🔒

Entryinfo

Created: 03/16/2026 22:28
Updated: 03/21/2026 16:36
Changes: 03/16/2026 22:28 (65), 03/17/2026 03:36 (1), 03/21/2026 16:36 (1)
Complete: 🔍
Cache ID: 216::103

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

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