CVE-2021-40655
D-Link Routers (DIR, DWR, DSR) · Home and small-office routers, cameras and IoT
D-Link DIR-605 Router Information Disclosure Vulnerability
At a glance
Exploited. Added to CISA’s catalog of exploited vulnerabilities on May 16, 2024.
End-of-life product: no patch is coming. Remove it or isolate it from the network.
Affected product: D-Link Routers (DIR, DWR, DSR) (category Home and small-office routers, cameras and IoT, indicative classification). Name in CISA’s catalog: D-Link DIR-605 Router.
What should I do?
This product has reached end of life: no patch is coming. Remove it or isolate it from the network.
Deadline set by CISA for US federal agencies: 21 days (due June 6, 2024). It only binds those agencies, but it is a useful measure of urgency.
- D-Link security advisories page (general page, not the advisory for this vulnerability)
- The vendor’s specific advisory is listed in the NVD references: CVE-2021-40655 on the NVD website.
Original text of the required action (CISA)
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.
Timeline
- Vulnerability published Publication date (NVD)
- Exploitation confirmed Added to CISA’s KEV catalog
- CISA deadline Remediation deadline set for US federal agencies
The facts, with their sources
- Exploitation confirmed
- Yes, on May 16, 2024 Date added to the catalog of exploited vulnerabilities. Exploitation itself may have started earlier. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
- Ransomware
- No known use to date That does not guarantee it is not being used: the information is not public. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
- Hunt for compromise
- Not requested by CISA Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
- CISA required action
- This product has reached end of life: no patch is coming. Remove it or isolate it from the network. Rewritten by this site from CISA’s original text. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
- CISA deadline
- June 6, 2024, 21 days Set for US federal agencies: a measure of urgency, not an obligation elsewhere. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
- Vulnerability published
- September 24, 2021 Source: National Vulnerability Database (NVD), collected September 29, 2026 at 15:00 UTC
- Product according to CISA
- D-Link DIR-605 Router Filed by this site under “Home and small-office routers, cameras and IoT” (indicative classification). Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
- CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N Technical detail of the score: attack vector, complexity, impact. Source: National Vulnerability Database (NVD), collected September 29, 2026 at 15:00 UTC
Severity and activity
FIRST’s EPSS model. Since exploitation is already confirmed, this figure is mostly useful to compare activity. Collected Sep 29, 2026.
Description
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
Official description from the NVD, collected Sep 29, 2026. CVE® description © The MITRE Corporation.
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.
Summary from CISA (KEV catalog).
CERT-FR advisories
No advisory among the latest CERT-FR publications this site follows. That does not mean there are none.
Information reused under the Open Licence 2.0 (Etalab); the date of last update is shown for each advisory. This site is neither affiliated with nor endorsed by ANSSI.
Sources for this page
- CISA KEV catalog: exploitation, date added, required action, deadline, ransomware.
- NVD (NIST): CVSS severity, publication date, description, vendor references.
- EPSS (FIRST): probability of exploitation.
- CERT-FR: advisories and alerts (in French).
- Brand and category: indicative classification by this site (method).