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CRITICAL severity

CVE-2026-123961 — Totolink Ca300-Poe Firmware

CRITICAL

CVE-2026-123961 is a critical-severity (CVSS 9.9) Buffer Overflow vulnerability in totolink ca300-poe firmware. The records list no fixed version yet; check the vendor advisory below and apply the mitigations in the meantime.

A security vulnerability has been detected in TOTOLINK CA300-PoE 6.2c.884. This impacts the function setWiFiBasicConfig of the file /cgi-bin/cstecgi.cgi. The manipulation of the argument…

Published
Updated
Affected
1 product
Patched
See advisory
Exploits
None indexed
Exploitation data as of Nov 7, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Description

A security vulnerability has been detected in TOTOLINK CA300-PoE 6.2c.884. This impacts the function setWiFiBasicConfig of the file /cgi-bin/cstecgi.cgi. The manipulation of the argument KeyStr leads to buffer overflow. The attack may be initiated remotely. The exploit has been disclosed publicly and may be used.

Affected Products

1 product · 1 configurations
OS
ca300-poe firmwaretotolink
all

Detection & mitigation playbook

Vendor / appliance

  1. Detect

    Inventory every totolink ca300-poe firmware deployment and check each version against the affected-products list above.

  2. Remediation status

    The records we use list no fixed version for CVE-2026-123961. Check the totolink ca300-poe firmware advisory for a patched release, and apply the workarounds below until you can upgrade.

  3. Mitigate without a patch

    Constrain what reaches the vulnerable code: limit the size and shape of untrusted input, isolate the affected component in a sandboxed or least-privileged process, and enable the platform's memory-safety mitigations (ASLR, stack protector, hardened allocator) so an out-of-bounds access is more likely to fail closed than to be exploitable. Alongside that, restrict the management interface to trusted networks and apply the vendor's recommended configuration mitigations.

Frequently Asked Questions

A security vulnerability has been detected in TOTOLINK CA300-PoE 6.2c.884. This impacts the function setWiFiBasicConfig of the file /cgi-bin/cstecgi.cgi. The manipulation of the argument KeyStr leads to buffer overflow. The attack may be initiated remotely. The exploit has been disclosed publicly and may be used.
O3 Security · Runtime Protection

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