discourse message_bus 对路径名的限制不恰当（路径遍历）

CVE编号

CVE-2021-43840

利用情况

暂无

补丁情况

N/A

披露时间

2021-12-18

漏洞描述

message_bus is a messaging bus for Ruby processes and web clients. In versions prior to 3.3.7 users who deployed message bus with diagnostics features enabled (default off) are vulnerable to a path traversal bug, which could lead to disclosure of secret information on a machine if an unintended user were to gain access to the diagnostic route. The impact is also greater if there is no proxy for your web application as the number of steps up the directories is not bounded. For deployments which uses a proxy, the impact varies. For example, If a request goes through a proxy like Nginx with `merge_slashes` enabled, the number of steps up the directories that can be read is limited to 3 levels. This issue has been patched in version 3.3.7. Users unable to upgrade should ensure that MessageBus::Diagnostics is disabled.

解决建议

建议您更新当前系统或软件至最新版，完成漏洞的修复。

参考链接
https://github.com/discourse/message_bus/commit/9b6deee01ed474c7e9b5ff65a06bb...
https://github.com/discourse/message_bus/security/advisories/GHSA-xmgj-5fh3-xjmm

受影响软件情况

#	类型	厂商	产品	版本	影响面
1
	运行在以下环境
	应用	discourse	message_bus	*		Up to (excluding) 3.3.7

CVSS3评分 4.4

• 攻击路径 网络
• 攻击复杂度 高
• 权限要求 高
• 影响范围 未更改
• 用户交互 无
• 可用性 无
• 保密性 高
• 完整性 无

CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:N/A:N CWE-ID 漏洞类型 CWE-22 对路径名的限制不恰当（路径遍历）