CVE-2026-93847— Improper post type validation on scheduled post endpoints

Quick assessment

Affected

Mattermost Mattermost

Exploitation

No confirmed in-the-wild exploitation; assess based on exposure

Recommended action

Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

Mattermost 11.7.x 至 11.7.10 版本在定时帖子的创建与发布路径中，未能对保留的系统帖子类型进行验证，这导致已认证的频道成员可通过定时帖子端点发布消息，使其渲染为受信任的系统事件。Mattermost 安全公告编号：MMSA-2026-00732。

CVSS 3.5 · Low EPSS 0.17% · P7 Updated Oct 26, 2026

Possible ATT&CK Techniques 2 AI

T1056.004 · Credential API Hooking T1070.001

Affected Version Matrix 3

Vendor	Product	Version Range	Status
Mattermost	Mattermost	`11.7.0≤ 11.7.10`	affected
		`11.11.0`	unaffected
		`11.7.11`	unaffected

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Vulnerability Information

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Vulnerability Title

Improper post type validation on scheduled post endpoints

Source: CVE Program / CVE List V5

Vulnerability Description

Mattermost versions 11.7.x <= 11.7.10 fail to validate reserved system post types on the scheduled post creation and publication paths which allows an authenticated channel member to publish messages rendering as trusted system events via the scheduled post endpoint.. Mattermost Advisory ID: MMSA-2026-00732

Source: CVE Program / CVE List V5

CVSS Information

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N

Source: CVE Program / CVE List V5

Vulnerability Type

授权机制不正确

Source: CVE Program / CVE List V5

Affected Products

Vendor	Product	Affected Versions	CPE	Subscribe
Mattermost	Mattermost	11.7.0 ~ 11.7.10	-

II. Public POCs for CVE-2026-93847

#	POC Description	Source Link	Shenlong Link

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III. Intelligence Information for CVE-2026-93847

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https://www.cve.org/CVERecord?id=CVE-2026-93847

Same Patch Batch · Mattermost · 2026-10-26 · 6 CVEs total

CVE-2026-116516	6.5 MEDIUM	Insufficient length validation when parsing Zoom chat transcriptions
CVE-2026-93849	6.5 MEDIUM	Mattermost allows authenticated users to trigger excessive memory allocation via crafted m
CVE-2026-93850	6.5 MEDIUM	Unbounded memory consumption during PDF text extraction
CVE-2026-93846	3.8 LOW	Team admin can escalate a team member's permissions via the team member roles endpoint
CVE-2026-93848	2.7 LOW	Mattermost OpenID discovery endpoint request bypasses outbound connection filtering, allow

IV. Related Vulnerabilities

Same product: Mattermost

Same vendor: Mattermost

Same weakness: CWE-863