CVE-2021-27173
mediumpriority · track · 34OT risk · elevatedEPSS 0.127 · 96 %ileEUUSEPSS · scored 2026-10-27
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
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (2)
Products and version ranges known to be affected.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (5)
External citations — patches, advisories, analysis.
- https://nvd.nist.gov/vuln/detail/CVE-2021-27173cnnvd
- https://pierrekim.github.io/blog/2021-01-12-fiberhome-ont-0day-vulnerabilities.htmlPatchcnnvd
- https://pierrekim.github.io/blog/2021-01-12-fiberhome-ont-0day-vulnerabilities.html#cnnvd
- https://pierrekim.github.io/blog/2021-01-12-fiberhome-ont-0day-vulnerabilities.html#httpd-infoleakenisa_euvd
- https://pierrekim.github.io/blog/2021-01-12-fiberhome-ont-0day-vulnerabilities.html#httpd-infoleakExploitThird Party Advisorynvd
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