Actively exploited

CVE-2020-24363 TP-link TL-WA855RE Missing Authentication for Critical Function Vulnerability

TP-link TL-WA855RE contains a missing authentication for critical function vulnerability. This vulnerability could allow an unauthenticated attacker (on the same network) to submit a TDDP_RESET POST request for a factory reset and reboot. The attacker can then obtain incorrect access control by setting a new administrative password. The impacted products could be end-of-life (EoL) and/or end-of-service (EoS). Users should discontinue product utilization.

From the CISA KEV catalogue version 2026.11.06, with Cybergen analysis. Updated 6 Nov 2026.

Our Assessment

Should You Worry?

Patch urgentlyCybergen assessment

CISA confirmed exploitation in the wild and added it to the Known Exploited Vulnerabilities catalogue on 2 Sep 2025.
Rated High severity (CVSS 8.8, scored by CISA).
It has been in the catalogue for 430 days. Systems still unpatched now have almost certainly been scanned for it.

The Vulnerability

What It Is

TP-Link TL-WA855RE V5 20200415-rel37464 devices allow an unauthenticated attacker (on the same network) to submit a TDDP_RESET POST request for a factory reset and reboot. The attacker can then obtain incorrect access control by setting a new administrative password.

From Watch to Action

What To Do Now

1
Find it
Search your asset inventory and external attack surface for TP-Link TL-WA855RE. Include cloud images, appliances and anything a supplier runs for you.
Attack Surface Management
2
Fix it
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Vulnerability Management
3
Hunt for compromise
If an affected system was reachable before you patched, assume it may have been hit. Check logs, new accounts, web shells and outbound connections from the date of exposure.
Incident Response
4
Prove it is fixed
Rescan or test the system after patching. Upgrades that fail silently and forgotten secondary instances are common.
Penetration Testing

Vendor Advisories

Regulation

The Compliance Clock

Cyber EssentialsRated high, so if it affects devices in your Cyber Essentials scope, the update must be installed within 14 days of the vendor releasing it.NIS2If exploitation causes a significant incident, essential and important entities owe their CSIRT an early warning within 24 hours and a notification within 72 hours.DORAFinancial entities must classify ICT incidents and send an initial notification for a major incident within strict deadlines, with exploited flaws a common cause.US federal (BOD 22-01)Federal civilian agencies had until 23 Sep 2025 to remediate. A sensible benchmark for everyone else.

General guidance, not legal advice. Your obligations depend on your sector, scope and jurisdiction.

Stay Ahead

More Exploited TP-Link Flaws

All 6 exploited TP-Link vulnerabilities

Not Sure If You Are Exposed?

Our attack surface and vulnerability teams can check your internet-facing estate for CVE-2020-24363 and every other exploited flaw on the list.

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CLOUD SECURITY

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REGULATED SERVICES

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DATA & APPLICATIONS

PEOPLE & EMAIL

FOR VENDORS

CVE-2020-24363 TP-link TL-WA855RE Missing Authentication for Critical Function Vulnerability

Should You Worry?

What It Is

What To Do Now

Find it

Fix it

Hunt for compromise

Prove it is fixed

Vendor Advisories

The Compliance Clock

More Exploited TP-Link Flaws

Not Sure If You Are Exposed?

Sources