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CVE-2026-82539 is a stack-based buffer overflow in the MAC Filtering component of TOTOLINK A720R firmware 4.1.5cu.630_B20250509. The setMacFilterRules handler copies the user-controlled desc argument into a fixed-size stack buffer without adequate bounds checking. An oversized value corrupts stack memory; the absence of stack canaries and position-independent execution support facilitates execution-flow control.
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No valid public exploits. Mallory filtered out 1 candidate as fakes, detection scripts, or README-only repos.
All candidate exploits were filtered out by Mallory's validation.
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8 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
A stack-based buffer overflow in the TOTOLINK A720R router's MAC-filtering functionality. An oversized desc parameter overflows a fixed-size stack buffer in cstecgi.cgi, enabling reliable control of execution flow. The demonstrated exploitation redirects execution to existing code that enables the device's Telnet service, creating a route to a root-level foothold through the embedded Telnet backdoor.
A remotely exploitable memory-corruption vulnerability in the MAC Filtering component of TOTOLINK A720R firmware 4.1.5cu.630_B20250509. Manipulation of the desc argument to the setMacFilterRules function in cstecgi.cgi triggers the flaw.
A remotely reachable memory-corruption vulnerability in the MAC Filtering component of TOTOLINK A720R firmware 4.1.5cu.630_B20250509. Manipulation of the desc argument to the setMacFilterRules function in cstecgi.cgi can trigger the flaw; exploitation requires high privileges according to the supplied CVSS vector.
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Every observed campaign linking this CVE to a named adversary.
Malware families riding this exploit, with evidence and IOCs.
YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.
Cross-references every affected SKU, including bundled OEM variants.
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