Vulnerability-Lookup

GHSA-QCVH-Q94P-MXJX

Vulnerability from github – Published: 2026-05-04 18:30 – Updated: 2026-05-06 12:30

Details

D-Link DIR-600L Hardware Revision B1 (End-of-Life) contains a hardcoded telnet backdoor. The device starts a telnet daemon at boot via /bin/telnetd.sh with the username "Alphanetworks" and the static password "wrgn61_dlwbr_dir600L" read from /etc/alpha_config/image_sign. The custom telnetd binary accepts a -u user:password flag, and the custom login binary uses strcmp() to validate credentials. Successful authentication grants an unauthenticated attacker on the local network a root shell with full administrative control. The device has reached End-of-Life (EOL) and will not receive patches.

Severity ?

9.8 (Critical)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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{
  "affected": [],
  "aliases": [
    "CVE-2026-42374"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-798"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-04T17:16:25Z",
    "severity": "CRITICAL"
  },
  "details": "D-Link DIR-600L Hardware Revision B1 (End-of-Life) contains a hardcoded telnet backdoor. The device starts a telnet daemon at boot via /bin/telnetd.sh with the username \"Alphanetworks\" and the static password \"wrgn61_dlwbr_dir600L\" read from /etc/alpha_config/image_sign. The custom telnetd binary accepts a -u user:password flag, and the custom login binary uses strcmp() to validate credentials. Successful authentication grants an unauthenticated attacker on the local network a root shell with full administrative control.\u00a0 The device has reached End-of-Life (EOL) and will not receive patches.",
  "id": "GHSA-qcvh-q94p-mxjx",
  "modified": "2026-05-06T12:30:24Z",
  "published": "2026-05-04T18:30:31Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-42374"
    },
    {
      "type": "WEB",
      "url": "https://www.securin.io/zero-day/cve-2026-42374-hardcoded-telnet-backdoor-in-d-link-dir-600l-b1-end-of-life-"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-42374 (GCVE-0-2026-42374)

Vulnerability from cvelistv5 – Published: 2026-05-04 16:00 – Updated: 2026-05-05 12:43 Unsupported When Assigned

Title

D-Link DIR-600L B1 Hardcoded Telnet Backdoor Credentials

Summary

Severity ?

9.8 (Critical)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CWE

CWE-798 - Use of Hard-coded Credentials

Assigner

securin

References

URL

Tags

https://www.securin.io/zero-day/cve-2026-42374-ha…

Impacted products

	Vendor	Product	Version
	D-Link	DIR-600L Firmware	Affected: B1 (custom) cpe:2.3:o:dlink:dir-600l_firmware::::::::

Date Public ?

2026-04-24 00:00

Credits

Arjun Basnet from Securin Labs

Show details on NVD website

JSON

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    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-42374",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-05-05T03:56:22.870524Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
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        "providerMetadata": {
          "dateUpdated": "2026-05-05T12:43:29.118Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
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          }
        ],
        "title": "CISA ADP Vulnrichment"
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    ],
    "cna": {
      "affected": [
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          "cpes": [
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          ],
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      "metrics": [
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            "attackVector": "NETWORK",
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            "confidentialityImpact": "HIGH",
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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

GHSA-QCVH-Q94P-MXJX

CVE-2026-42374 (GCVE-0-2026-42374)

Tags

Sightings

Nomenclature