CVE-2021-27171 in the critical feed json
An issue was discovered on FiberHome HG6245D devices through RP2613.
published 2021-02-10 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-13938
- cvss
- 9.8
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 18.0%
- EPSS 18.0% chance of exploitation in 30 days, percentile 97%
- public exploits
- 0
- none known
Summary
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).
Exploit prediction
18.04% chance of exploitation in the next 30 days, higher than 97% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- pierrekim.github.io https://pierrekim.github.io/blog/2021-01-12-fiberhome-ont-0day-vulnerabilities.html#telnet-cli-privilege-escalation referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 10.0 | AV:N/AC:L/Au:N/C:C/I:C/A:C |
Classification
- Weakness
-
- CWE-787 Out-of-bounds Write
References
-
pierrekim.github.io
/blog/2021-01-12-fiberhome-ont-0day-vulnerabilities.html#telnet-cli-privilege-escalation
exploit, third-party-advisory
Sources
- CVE List CVE-2021-27171
- NVD CVE-2021-27171
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.