VDB-432021 · Submit #1033673 · CVE-2026-123958

TOTOLINK CA300-PoE 6.2c.884 /cgi-bin/cstecgi.cgi setLanConfig lanDns/lanSecDns/langType buffer overflow

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
9.4	$0-$5k	0.83+

Summaryinfo

A vulnerability identified as very critical has been detected in TOTOLINK CA300-PoE 6.2c.884. The impacted element is the function setLanConfig of the file /cgi-bin/cstecgi.cgi. Performing a manipulation of the argument lanDns/lanSecDns/langType results in buffer overflow. This vulnerability is identified as CVE-2026-123958. The attack can be initiated remotely. Additionally, an exploit exists.

Detailsinfo

A vulnerability, which was classified as very critical, was found in TOTOLINK CA300-PoE 6.2c.884. This affects the function setLanConfig of the file /cgi-bin/cstecgi.cgi. The manipulation of the argument lanDns/lanSecDns/langType with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer. This is going to have an impact on confidentiality, integrity, and availability.

The advisory is shared at lavender-bicycle-a5a.notion.site. This vulnerability is uniquely identified as CVE-2026-123958. The exploitability is told to be easy. It is possible to initiate the attack remotely. Technical details and a public exploit are known. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 11/06/2026).

The exploit is shared for download at lavender-bicycle-a5a.notion.site. It is declared as proof-of-concept.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Vendor

TOTOLINK

Name

CA300-PoE

Version

6.2c.884

License

commercial

Website

Vendor: https://www.totolink.net/

CPE 2.3info

🔒

CPE 2.2info

🔒

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.9
VulDB Meta Temp Score: 9.4

VulDB Base Score: 9.9
VulDB Temp Score: 9.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Buffer overflow
CWE: CWE-120 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Access: Public
Status: Proof-of-Concept
Download: 🔒
Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

11/06/2026 Advisory disclosed
11/06/2026 +0 days VulDB entry created
11/06/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: totolink.net

Advisory: lavender-bicycle-a5a.notion.site
Status: Confirmed

CNA: VulDB
CVE: CVE-2026-123958 (🔒)

GCVE (CVE): GCVE-0-2026-123958
GCVE (VulDB): GCVE-100-432021
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 11/06/2026 18:12
Changes: 11/06/2026 18:12 (55)
Complete: 🔍
Submitter: wxhwxhwxh_mie
Cache ID: 216::103

Submitinfo

Accepted

Submit #1033673: TOTOLINK CA300-PoE CA300-PoE_Firmware V6.2c.884 Buffer Overflow (by wxhwxhwxh_mie)