websafe-kb/07-framework-security/platforms/mattermost/cases/mattermost-mmsa-2026-00578.md

---
title: "MMSA-2026-00578"
system_id: "mattermost"
category: "platforms"
advisory_mode: "core"
published_date: "2026-02-23"
updated_date: "2026-02-23"
severity: "medium"
exploit_status: "unknown"
source_confidence: "official"
verification_status: "triage-manual"
verification_mode: "synthetic"
artifact_mode: "synthetic"
last_run_id: ""
target_types:
  - "lab-local"
  - "lab-public"
  - "authorized-third-party"
allow_public_validation: "yes, with ownership or explicit authorization"
authorization_prerequisite: "asset ownership proof or explicit written authorization"
minimal_validation: "read-only probe, controlled payload, reversible test"
aliases:
  - "MMSA-2026-00578"
affected_versions:
  - "11.2.x <= 11.2.2"
  - "10.11.x <= 10.11.10"
  - "11.4.x <= 11.4.0"
  - "11.3.x <= 11.3.1"
fixed_versions:
  - "11.5.0"
  - "11.2.3"
  - "10.11.11"
  - "11.4.1"
  - "11.3.2"
entity_refs:
  - "mattermost:system:root-system"
  - "mattermost--project--mattermost-server:project:affected-component"
secure_code_topics:
  - "authz-server-side-recheck"
  - "xss-output-encoding"
  - "token-cookie-storage"
primary_source: "https://securityupdates.mattermost.com/security_updates.json"
---

# MMSA-2026-00578

## 本地实证状态

- 实证状态: `triage-manual`
- 实证方式: `synthetic`
- Artifact 模式: `synthetic`
- 最近运行: `-`
- 浏览器证据: `missing`
- Run Bundle: `-`

## 事件层

- Canonical ID: `mattermost--MMSA-2026-00578`
- 系统: `mattermost`
- 严重度: `medium`
- 来源置信度: `official`
- 官方主源: https://securityupdates.mattermost.com/security_updates.json
- 影响版本: `11.2.x <= 11.2.2, 10.11.x <= 10.11.10, 11.4.x <= 11.4.0, 11.3.x <= 11.3.1`
- 修复版本: `11.5.0, 11.2.3, 10.11.11, 11.4.1, 11.3.2`

## 对象与版本映射

- Advisory Scope: `package`
- 影响对象: `Mattermost Server`
- Entity Refs: `mattermost, mattermost--project--mattermost-server`
- 版本置信度: `high`
- 版本缺口: `-`
- 版本证据源: `https://securityupdates.mattermost.com/security_updates.json`

## 受控验证流程

- Workflow ID: `mattermost--MMSA-2026-00578--workflow`
- 漏洞家族: `xss`
- 入口面: `web-ui-render-path`
- 需要角色: `editor-or-admin`
- 触发向量: 对 `xss` 家族入口投递最小化、可审计、可回滚的受控输入，比较修复前后差异。
- 请求/页面入口: `/admin/editor, /preview, /rendered-content`
- 输入形态: 受控 HTML/Markdown/富文本输入，观察渲染上下文是否失去编码或净化。
- 预期不安全行为: 输入在目标上下文执行或被浏览器解释为主动内容。

## 其他来源

- 无额外来源

## 证据点与补丁验证

### 服务端证据点

- 应用日志中的命中路径、鉴权决策和异常栈
- 反向代理或边界层日志中的请求头、来源 IP 与路由决策

### 浏览器证据点

- 基线截图与攻击后截图的 DOM/视觉差异
- console、network 与 response metadata 中的异常信号

### 数据库/文件系统证据点

- 数据库中新增/越权读取的测试数据
- 文件系统中新增上传样本、缓存条目或越权读取痕迹

### 检测信号

- WAF / reverse proxy 异常日志、访问日志和告警
- 应用审计日志中的权限错误、重定向异常、模板渲染或上传落盘事件

### 补丁验证步骤

- 确认目标版本从 `11.2.x <= 11.2.2, 10.11.x <= 10.11.10, 11.4.x <= 11.4.0` 升级或回移到 `11.5.0`。
- 保留同一组受控输入，在修复前后分别执行并比对响应、日志与浏览器证据。
- 确认修复后仅保留预期业务行为，不再触发越权、回显、异常渲染或错误请求。
- 补充 `xss` 族自动化回归，避免同类路径在插件、主题或代理链中回归。

### 实验安全备注

- 只使用回环地址、哨兵目标、无害样本或可回滚测试数据。
- 禁止造成持久破坏、越权下载真实数据或不可回滚 side effect。
- 如需浏览器证据，保留 baseline / proof 两份快照以及 console / network 记录。

## 实验层

- 仅用于自有资产、测试环境或已明确授权目标。
- 允许公网可达目标，但必须满足资产归属或明确授权前提。
- 最小化验证方式: 最小化验证、只读探测、可审计回显、受控注入。
- 若该案例涉及插件、模块或扩展，应同时检查供应链与升级策略。
- 禁止场景: 无归属证明或无明确授权的公网目标；知名公共网站或与测试无关的第三方资产；会造成持久破坏、数据越权下载或不可回滚影响的动作

## 修复示例

- [javascript-typescript:authz-server-side-recheck](/Users/x/websafe/05-defense/secure-code/javascript-typescript/authz-server-side-recheck.md)
- [nodejs:authz-server-side-recheck](/Users/x/websafe/05-defense/secure-code/nodejs/authz-server-side-recheck.md)
- [java:authz-server-side-recheck](/Users/x/websafe/05-defense/secure-code/java/authz-server-side-recheck.md)
- [php:authz-server-side-recheck](/Users/x/websafe/05-defense/secure-code/php/authz-server-side-recheck.md)
- [python:authz-server-side-recheck](/Users/x/websafe/05-defense/secure-code/python/authz-server-side-recheck.md)
- [ruby:authz-server-side-recheck](/Users/x/websafe/05-defense/secure-code/ruby/authz-server-side-recheck.md)
- [csharp:authz-server-side-recheck](/Users/x/websafe/05-defense/secure-code/csharp/authz-server-side-recheck.md)
- [go:authz-server-side-recheck](/Users/x/websafe/05-defense/secure-code/go/authz-server-side-recheck.md)
- [javascript-typescript:xss-output-encoding](/Users/x/websafe/05-defense/secure-code/javascript-typescript/xss-output-encoding.md)
- [nodejs:xss-output-encoding](/Users/x/websafe/05-defense/secure-code/nodejs/xss-output-encoding.md)
- [java:xss-output-encoding](/Users/x/websafe/05-defense/secure-code/java/xss-output-encoding.md)
- [php:xss-output-encoding](/Users/x/websafe/05-defense/secure-code/php/xss-output-encoding.md)
- [python:xss-output-encoding](/Users/x/websafe/05-defense/secure-code/python/xss-output-encoding.md)
- [ruby:xss-output-encoding](/Users/x/websafe/05-defense/secure-code/ruby/xss-output-encoding.md)
- [csharp:xss-output-encoding](/Users/x/websafe/05-defense/secure-code/csharp/xss-output-encoding.md)
- [go:xss-output-encoding](/Users/x/websafe/05-defense/secure-code/go/xss-output-encoding.md)
- [javascript-typescript:token-cookie-storage](/Users/x/websafe/05-defense/secure-code/javascript-typescript/token-cookie-storage.md)
- [nodejs:token-cookie-storage](/Users/x/websafe/05-defense/secure-code/nodejs/token-cookie-storage.md)
- [java:token-cookie-storage](/Users/x/websafe/05-defense/secure-code/java/token-cookie-storage.md)
- [php:token-cookie-storage](/Users/x/websafe/05-defense/secure-code/php/token-cookie-storage.md)
- [python:token-cookie-storage](/Users/x/websafe/05-defense/secure-code/python/token-cookie-storage.md)
- [ruby:token-cookie-storage](/Users/x/websafe/05-defense/secure-code/ruby/token-cookie-storage.md)
- [csharp:token-cookie-storage](/Users/x/websafe/05-defense/secure-code/csharp/token-cookie-storage.md)
- [go:token-cookie-storage](/Users/x/websafe/05-defense/secure-code/go/token-cookie-storage.md)