CVE-2026-109506: Improper Authentication in Multiple TP-Link WiFi Repeaters

Severity: medium (CVSS 5.9 v4.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-10-14 · updated 2026-10-15
Weakness: CWE-287

Description

Multiple TP-Link Wi-Fi range extenders use a custom, reversible XOR-and-dictionary transformation in the HTTP web-management login flow. An unauthenticated attacker on the same local network who can capture the network traffic associated with legitimate administrator login may be able to derive an alternative credential value that produces the same accepted authentication result and use it to authenticate to the device’s web-management interface with administrator privileges. Exploitation requires the management login to use HTTP and the attacker to observe the session key, dictionary, and login value associated with a legitimate administrator login. Successful exploitation may allow an unauthenticated adjacent attacker to gain administrator access to the affected device and modify exposed configuration settings.

Affected products

TP-Link Systems Inc. RE190 v5: before V5_260904 — fixed in V5_260904
TP-Link Systems Inc. RE200 v5: before V5_260904 — fixed in V5_260904
TP-Link Systems Inc. RE205 v4: before V4_260904 — fixed in V4_260904
TP-Link Systems Inc. RE215 v1: before V1_260904 — fixed in V1_260904
TP-Link Systems Inc. RE220 v3: before V3_260904 — fixed in V3_260904
TP-Link Systems Inc. RE230 v2: before V2_260904 — fixed in V2_260904
TP-Link Systems Inc. RE300 v2: before V2_260904 — fixed in V2_260904
TP-Link Systems Inc. RE305 v4: before V4_260904 — fixed in V4_260904
TP-Link Systems Inc. RE315 v1: before V1_260904 rel3959 — fixed in V1_260904 rel3959
TP-Link Systems Inc. RE330 v1: before V1_260904 — fixed in V1_260904
TP-Link Systems Inc. RE335 v1: before V1_260904 — fixed in V1_260904
TP-Link Systems Inc. RE365 v2: before V2_260904 — fixed in V2_260904
TP-Link Systems Inc. RE365 v3: before V3_260904 — fixed in V3_260904
TP-Link Systems Inc. RE450 v4.8: before V4_260915 — fixed in V4_260915
TP-Link Systems Inc. RE550 v1: before V1_260915 — fixed in V1_260915
TP-Link Systems Inc. RE750C v4: before V4_260904 — fixed in V4_260904

How to fix

Upgrade to a fixed version: TP-Link Systems Inc. RE190 v5 V5_260904; TP-Link Systems Inc. RE200 v5 V5_260904; TP-Link Systems Inc. RE205 v4 V4_260904; TP-Link Systems Inc. RE215 v1 V1_260904; TP-Link Systems Inc. RE220 v3 V3_260904; TP-Link Systems Inc. RE230 v2 V2_260904; TP-Link Systems Inc. RE300 v2 V2_260904; TP-Link Systems Inc. RE305 v4 V4_260904; TP-Link Systems Inc. RE315 v1 V1_260904 rel3959; TP-Link Systems Inc. RE330 v1 V1_260904; TP-Link Systems Inc. RE335 v1 V1_260904; TP-Link Systems Inc. RE365 v2 V2_260904. Check the vendor advisory for mitigations.

References

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