Exploited. On CISA's list since 2022-03-31.

Dasan GPON Routers Authentication Bypass Vulnerability

CVE-2018-10561 · Dasan Gigabit Passive Optical Network (GPON) Routers · Published 2018-05-04

How bad would it be?

9.8 out of 10

CVSS rates it critical: about as damaging as flaws get.

How likely is it to be used?

93%

Estimated chance of exploitation in the next 30 days, among the top 1% of all scored flaws (EPSS, 2026-10-29).

Is it already being used?

Yes

CISA has seen it exploited in real attacks. For US government agencies the fix is deadline passed 1653 days ago (2022-04-21).

What CISA says to do

The impacted product is end-of-life and should be disconnected if still in use.

Dasan GPON Routers contain an authentication bypass vulnerability. When combined with CVE-2018-10562, exploitation can allow an attacker to perform remote code execution.

nvd.nist.gov

What the flaw is

An issue was discovered on Dasan GPON home routers. It is possible to bypass authentication simply by appending "?images" to any URL of the device that requires authentication, as demonstrated by the /menu.html?images/ or /GponForm/diag_FORM?images/ URI. One can then manage the device.

From the NVD.

Learn this

Explore this week’s weaknesses and all learning topics

Understand the kind of weakness behind this flaw. These resources teach the weakness, rather than reproduce this specific CVE. Follow the vendor's advice above to fix the affected product.

Authentication weaknesses

The application does not reliably check that someone is who they claim to be.

CWE-287 · CISA KEV; NVD record: 134c704f-9b21-4f2e-91b3-4a467353bcc0; NVD record: nvd@nist.gov

Reading and practice labs · Free account for labs. Basic HTTP knowledge; some labs use Burp Suite.

Explore the labs at PortSwigger Web Security Academy How it is prevented

CWE is a catalogue of weakness types. Labels come from the sources shown and can differ or change. Resource matches reviewed 16 October 2026.

On SentryFeed

No story in the last 14 days has mentioned it.

Exploited flaws from CISA's KEV catalogue. Chance of exploitation from EPSS by FIRST. Descriptions and scores from the NVD. This product uses the NVD API but is not endorsed or certified by the NVD.