---
id: "CVE-2026-13411"
kind: "vulnerability"
aliases: ["CVE-2026-13411"]
title: "Mattermost Playbooks: null import condition crashes plugin for all users"
severity: "medium"
cvss: 4.3
epss: 0.00321
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["mattermost", "package", "playbooks-plugin", "self-hosted"]
not_affected_if: ["auth-required", "managed-hosting"]
published_at: "2026-10-22T11:17:52+00:00"
first_seen_at: "2026-10-23T21:57:31+00:00"
updated_at: "2026-10-25T04:37:24+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-13411", "first_seen_at": "2026-10-23T21:57:31+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2026-13411", "first_seen_at": "2026-10-24T07:15:51+00:00"}]
---

# Mattermost Playbooks: null import condition crashes plugin for all users

Mattermost versions 11.7.x up to 11.7.11 fail to validate null elements when decoding playbook import conditions. An authenticated user can send a crafted import request with a null condition and crash the Playbooks plugin for the whole instance.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the Mattermost server version with `mattermost version` or the System Console and see whether it falls in 11.7.x up to 11.7.11.
- Confirm the Playbooks plugin is installed and enabled in the System Console under Plugin Management.

## Fix

- Upgrade Mattermost to a release newer than `11.7.11` that includes the MMSA-2026-00709 fix (exact fixed version unknown from sources).
- Until patched, restrict playbook import to trusted users.

## Timeline

- 2026-10-23T21:57:31+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-13411
- 2026-10-24T07:15:51+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2026-13411

## From the sources

Mattermost versions 11.7.x <= 11.7.11 fail to validate null elements when decoding playbook import conditions which allows an authenticated attacker to crash the Playbooks plugin instance-wide via a crafted import request containing a null condition. Mattermost Advisory ID: MMSA-2026-00709

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_