CVE-2026-5039 (GCVE-0-2026-5039)

Vulnerability from cvelistv5 – Published: 2026-04-23 16:10 – Updated: 2026-04-28 17:45
VLAI
Title
Predictable Default Cryptographic Key Used for DES Encryption in TP-Link TL-WL841N
Summary
TP-Link TL-WR841N v13 uses DES-CBC encryption in the TDDPv2 debug protocol with a cryptographic key derived from default web management credentials, making the key predictable if device is left in default configuration. A network-adjacent attacker can exploit this weakness to gain unauthorized access to the protocol, read debug data, modify certain device configuration values, and trigger device reboot, resulting in loss of integrity and a denial-of-service condition.
Severity
6.1 (Medium)
CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:L/VI:H/VA:H/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-23 17:38 UTC
CWE
  • CWE-1394 - Use of default cryptographic key
Assigner
TPLink CNA under the mitre root
CNA scorecard B 87/100 over 109 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
TP-Link Systems Inc. TL-WL841N v13 Affected: 0 , < 0.9.1 Build 20231120 Rel.62366 (custom)
guessed Create a notification for this product.
Credits
Ben Grinberg, Adiel Sol, Daniel Lubel, Erez Cohen, Nir Somech, Arad Inbar, Dream Group
Show details on NVD website
To clipboard 

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