CVE-2017-8415
However, the /etc/shadow file is a part of CRAM-FS filesystem which means that the user cannot change the password and hence a hardcoded hash in /etc/shadow is used to match the credentials provided by the user.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (3.93%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
An issue was discovered on D-Link DCS-1100 and DCS-1130 devices. The device has a custom telnet daemon as a part of the busybox and retrieves the password from the shadow file using the function getspnam at address 0x00053894. Then performs a crypt operation on the password retrieved from the user at address 0x000538E0 and performs a strcmp at address 0x00053908 to check if the password is correct or incorrect. However, the /etc/shadow file is a part of CRAM-FS filesystem which means that the user cannot change the password and hence a hardcoded hash in /etc/shadow is used to match the credentials provided by the user. This is a salted hash of the string "admin" and hence it acts as a password to the device which cannot be changed as the whole filesystem is read only.
- CVSS 3.1
- 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 3.93% probability · 90th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-798
- Affected
- dlink/dcs-1130 firmware · dlink/dcs-1100 firmware
- Source
- cve@mitre.org
References
- http://packetstormsecurity.com/files/153226/Dlink-DCS-1130-Command-Injection-CSRF-Stack-Overflow.htmlThird Party Advisory, VDB Entry
- https://github.com/ethanhunnt/IoT_vulnerabilities/blob/master/Dlink_DCS_1130_security.pdfNot Applicable, Third Party Advisory
- https://seclists.org/bugtraq/2019/Jun/8Mailing List, Third Party Advisory
- http://packetstormsecurity.com/files/153226/Dlink-DCS-1130-Command-Injection-CSRF-Stack-Overflow.htmlThird Party Advisory, VDB Entry
- https://github.com/ethanhunnt/IoT_vulnerabilities/blob/master/Dlink_DCS_1130_security.pdfNot Applicable, Third Party Advisory
- https://seclists.org/bugtraq/2019/Jun/8Mailing List, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.