SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2022-25219

A null byte interaction error has been discovered in the code that the telnetd_startup daemon uses to construct a pair of ephemeral passwords that allow a user to spawn a telnet service on the router, and to ensure that the telnet service persists upon…

HIGH 8.4EPSS 0.77%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.77%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

A null byte interaction error has been discovered in the code that the telnetd_startup daemon uses to construct a pair of ephemeral passwords that allow a user to spawn a telnet service on the router, and to ensure that the telnet service persists upon reboot. By means of a crafted exchange of UDP packets, an unauthenticated attacker on the local network can leverage this null byte interaction error in such a way as to make those ephemeral passwords predictable (with 1-in-94 odds). Since the attacker must manipulate data processed by the OpenSSL function RSA_public_decrypt(), successful exploitation of this vulnerability depends on the use of an unpadded RSA cipher (CVE-2022-25218).

CVSS 3.1
8.4 HIGHCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
0.77% probability · 55th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Affected
phicomm/k2 firmware · phicomm/k3 firmware · phicomm/k3c firmware · phicomm/k2g firmware · phicomm/k2p firmware
Source
vulnreport@tenable.com
EPSS trend
0%3%5%26 October 2026: 0.77%26 October 202626 October 2026

EPSS 0.8% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.