CVE-2021-27173 — HIGH (7.5)

Q: How severe is CVE-2021-27173?

CVE-2021-27173 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.

Q: Is there a patch for CVE-2021-27173?

Check the references section above for vendor advisories and patch information. Affected products include: Fiberhome Hg6245D Firmware, Fiberhome Hg6245D.

Vulnerability Description

An issue was discovered on FiberHome HG6245D devices through RP2613. There is a telnet?enable=0&key=calculated(BR0_MAC) backdoor API, without authentication, provided by the HTTP server. This will remove firewall rules and allow an attacker to reach the telnet server (used for the CLI).

CVSS Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality

NONE

Integrity

HIGH

Availability

NONE

Affected Products

Vendor	Product	Versions
Fiberhome	Hg6245D Firmware	<= rp2613
Fiberhome	Hg6245D	-

References

https://pierrekim.github.io/blog/2021-01-12-fiberhome-ont-0day-vulnerabilities.hExploitThird Party Advisory
https://pierrekim.github.io/blog/2021-01-12-fiberhome-ont-0day-vulnerabilities.hExploitThird Party Advisory

FAQ

What is CVE-2021-27173?

CVE-2021-27173 is a vulnerability with a CVSS score of 7.5 (HIGH). An issue was discovered on FiberHome HG6245D devices through RP2613. There is a telnet?enable=0&key=calculated(BR0_MAC) backdoor API, without authentication, provided by the HTTP server. This will rem...

How severe is CVE-2021-27173?

CVE-2021-27173 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2021-27173?

Check the references section above for vendor advisories and patch information. Affected products include: Fiberhome Hg6245D Firmware, Fiberhome Hg6245D.