Intelbras Router RF 301K 1.1.2 - Authentication Bypass

published 2026-01-28 9 mo ago modified 2026-07-28 3 mo ago also EUVD-2020-30886

cvss: 7.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 35%
public exploits: 0; none known

Intelbras Router RF 301K firmware version 1.1.2 contains an authentication bypass vulnerability that allows unauthenticated attackers to download router configuration files. Attackers can send a specific HTTP GET request to /cgi-bin/DownloadCfg/RouterCfm.cfg to retrieve sensitive router configuration without authentication.

CISA SSVC

Exploitation: Proof of concept is public
Automatable: yes
Technical impact: partial
Assessed: 9 mo ago (2026-01-28)

Exploit prediction

0.41% chance of exploitation in the next 30 days, higher than 35% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

exploit-db.com https://www.exploit-db.com/exploits/49126 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	4.0	8.7	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
CNA	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CNA	4.0	8.7	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected products

Intelbras Intelbras Router RF 301K

Classification

Weakness

CWE-306 Missing Authentication for Critical Functionality

References

exploit-db.com /exploits/49126
exploit
intelbras.com /pt-br/
product
vulncheck.com /advisories/intelbras-router-rf-k-authentication-bypass
third-party-advisory

Sources

CVE List CVE-2020-36963
NVD CVE-2020-36963

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.

Summary