9.1Critical
CVE-2026-51723
Incorrect access control in the UploadCustomModule function of TOTOLINK T6 4.1.5cu.748_B20211015 allows unauthenticated attackers to install a custom CGI module via sending a crafted POST request to /cgi-bin/cstecgi.cgi.
What this means for your business
- An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.3% chance of attack attempts being seen in the next 30 days, ranking above 21% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.
Scoring
- CVSS
- 9.1 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N- Weakness
- CWE-284
- Assigned by
- cve@mitre.org
Dates
- Published
- 2026-08-31
- Last modified
- 2026-09-02
- Sources
- NVD