CVE-2021-27171

9.8 criticalEPSS 18%

Critical (9.8) in fiberhome hg6245d firmware. EPSS 18% chance of exploitation in the next 30 days.

An issue was discovered on FiberHome HG6245D devices through RP2613. It is possible to start a Linux telnetd as root on port 26/tcp by using the CLI interface commands of ddd and shell (or tshell).

Severity

CVSS 3.1

9.8 critical

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

EPSS: 18% chance of exploitation in the next 30 days; higher than 97% of CVEs (scores of 2026-10-31)
CWE: CWE-787
Published: 2021-02-10
Modified: 2026-06-17
Record from: the NVD, synced 2026-10-19

Affected

fiberhome:hg6245d_firmware

References

https://pierrekim.github.io/blog/2021-01-12-fiberhome-ont-0day-vulnerabilities.html#telnet-cli-privilege-escalation
https://pierrekim.github.io/blog/2021-01-12-fiberhome-ont-0day-vulnerabilities.html#telnet-cli-privilege-escalation

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