CVE-2026-82539: TOTOLINK A720R MAC Filtering cstecgi.cgi setMacFilterRules memory corruption

Severity: critical (CVSS 9.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-08-30 · updated 2026-09-01
Weakness: CWE-119

Description

A vulnerability was determined in TOTOLINK A720R 4.1.5cu.630_B20250509. This impacts the function setMacFilterRules of the file cstecgi.cgi of the component MAC Filtering. Executing a manipulation of the argument desc can lead to memory corruption. The attack may be launched remotely. The exploit has been publicly disclosed and may be utilized.

Affected products

TOTOLINK A720R: 4.1.5cu.630_B20250509

References

https://github.com/Xernary/CVE-2026-82539
https://vuldb.com/cve/CVE-2026-82539
https://vuldb.com/submit/888696
https://vuldb.com/vuln/397055
https://vuldb.com/vuln/397055/cti
https://www.totolink.net/

Get alerted when CVE-2026-82539 or the next vulnerability affects your stack