High severity · published Aug 14, 2026
CVE-2026-19812
TOTOLINK A800R product.so cstecgi.cgi UploadCustomModule stack-based overflow
8.8
CVSS
0.9%
EPSS
No
On KEV
Description
A weakness has been identified in TOTOLINK A800R 4.1.2cu.5137_B20200730. This affects the function UploadCustomModule of the file /cgi-bin/cstecgi.cgi of the component product.so. This manipulation of the argument File causes stack-based buffer overflow. The attack is possible to be carried out remotely. The exploit has been made available to the public and could be used for attacks.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.9% · higher than 58% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
A8
A800R · TOTOLINK
4.1.2cu.5137_B20200730 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-19812
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-19812
github.com
https://github.com/panda666-888/vuls/blob/main/totolink/a800r/UploadCustomModule.md
vuldb.com
https://vuldb.com/cve/CVE-2026-19812
vuldb.com
https://vuldb.com/submit/869428
vuldb.com
https://vuldb.com/vuln/389948
vuldb.com
https://vuldb.com/vuln/389948/cti
www.totolink.net
https://www.totolink.net/
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