TOTOLINK EX1200T cstecgi.cgi setLanguageCfg stack-based overflow

published 2025-06-04 17 mo ago modified 2026-06-17 4 mo ago also EUVD-2025-16902

cvss: 9.8; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.3%; EPSS 1.3% chance of exploitation in 30 days, percentile 71%
public exploits: 0; none known

A vulnerability, which was classified as critical, has been found in TOTOLINK EX1200T 4.1.2cu.5232_B20210713. This issue affects the function setLanguageCfg of the file /cgi-bin/cstecgi.cgi. The manipulation of the argument LangType leads to stack-based buffer overflow. The attack may be initiated remotely. The exploit has been disclosed to the public and may be used.

CISA SSVC

Exploitation: Proof of concept is public
Automatable: yes
Technical impact: total
Assessed: 17 mo ago (2025-06-04)

Exploit prediction

1.34% chance of exploitation in the next 30 days, higher than 71% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

kn0sinna.notion.site https://kn0sinna.notion.site/TOTOLINK-EX1200T-stack-based-BufferOverflow-vulnerability-204b1876cd6e80709ce8dab4778dce55 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	4.0	9.3	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CNA	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA	3.0	9.8	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA	2.0	10.0	AV:N/AC:L/Au:N/C:C/I:C/A:C
CNA	4.0	9.3	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/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

TOTOLINK EX1200T

Classification

Weakness

CWE-121 Stack-based Buffer Overflow
CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer
CWE-787 Out-of-bounds Write

References

kn0sinna.notion.site /TOTOLINK-EX1200T-stack-based-BufferOverflow-vulnerability-204b1876cd6e80709ce8dab4778dce55
exploit, third-party-advisory
vuldb.com /?id.311087
vdb-entry, technical-description, third-party-advisory
vuldb.com /?ctiid.311087
signature, permissions-required
vuldb.com /?submit.588075
third-party-advisory, vdb-entry
totolink.net /
product

Sources

CVE List CVE-2025-5600
NVD CVE-2025-5600

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