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

Vulnerability from cvelistv5 – Published: 2026-04-23 16:10 – Updated: 2026-04-23 17:40
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
CWE
  • CWE-1394 - Use of default cryptographic key
Assigner
References
Impacted products
Vendor Product Version
TP-Link Systems Inc. TL-WL841N v13 Affected: 0 , < 0.9.1 Build 20231120 Rel.62366 (custom)
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  • 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.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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