CVE-2021-40655 D-Link DIR-605 Router Information Disclosure Vulnerability
D-Link DIR-605 routers contain an information disclosure vulnerability that allows attackers to obtain a username and password by forging a post request to the /getcfg.php page.
From the CISA KEV catalogue version 2026.11.06, with Cybergen analysis. Updated 6 Nov 2026.
Should You Worry?
- CISA confirmed exploitation in the wild and added it to the Known Exploited Vulnerabilities catalogue on 16 May 2024.
- Rated High severity (CVSS 7.5, scored by CISA).
- This product type is often exposed to the internet, which is where attackers scan for it first.
- It has been in the catalogue for 904 days. Systems still unpatched now have almost certainly been scanned for it.
What It Is
An informtion disclosure issue exists in D-LINK-DIR-605 B2 Firmware Version : 2.01MT. An attacker can obtain a user name and password by forging a post request to the / getcfg.php page
What To Do Now
- 1
Find it
Search your asset inventory and external attack surface for D-Link DIR-605 Router. Include cloud images, appliances and anything a supplier runs for you.
Attack Surface Management - 2
Fix it
This vulnerability affects legacy D-Link products. All associated hardware revisions have reached their end-of-life (EOL) or end-of-service (EOS) life cycle and should be retired and replaced per vendor instructions.
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
The Compliance Clock
General guidance, not legal advice. Your obligations depend on your sector, scope and jurisdiction.
Not Sure If You Are Exposed?
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