Totolink A8000R cstecgi.cgi setLanguageCfg missing authentication

published 2026-04-06 7 mo ago modified 2026-07-24 3 mo ago also EUVD-2026-19434

cvss: 7.3; 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 36%
public exploits: 0; none known

A vulnerability was identified in Totolink A8000R 5.9c.681_B20180413. This issue affects the function setLanguageCfg of the file /cgi-bin/cstecgi.cgi. Such manipulation of the argument langType leads to missing authentication. The attack can be launched remotely. The exploit is publicly available and might be used.

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: 7 mo ago (2026-04-07)

Exploit prediction

0.42% chance of exploitation in the next 30 days, higher than 36% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/skeetabc/CVE-TOTOLINK-A800R/blob/main/vuln1_auth_bypass.md referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	4.0	6.9	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
CNA	3.1	7.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:W/RC:R
CNA	3.0	7.3	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:W/RC:R
CNA	2.0	7.5	AV:N/AC:L/Au:N/C:P/I:P/A:P/E:POC/RL:W/RC:UR
CNA	4.0	5.5	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/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
CNA	3.1	7.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
CNA	2.0	7.5	AV:N/AC:L/Au:N/C:P/I:P/A:P

Affected products

Totolink A8000R

Classification

Weakness

CWE-306 Missing Authentication for Critical Functionality
CWE-287 Improper Authentication

References

github.com /skeetabc/CVE-TOTOLINK-A800R/blob/main/vuln1_auth_bypass.md
exploit
vuldb.com /vuln/355503
vdb-entry, technical-description
vuldb.com /vuln/355503/cti
signature, permissions-required
vuldb.com /submit/792433
third-party-advisory
totolink.net /
product

Sources

CVE List CVE-2026-5676
NVD CVE-2026-5676

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