CVE-2026-5039 Predictable Default Cryptographic Key Used for DES Encryption in TP-Link TL-WL841N
A predictable DES key in the TDDPv2 protocol allows network-adjacent attackers to read debug data, modify configurations, and cause device reboots.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-5039?
CVE-2026-5039 is a medium-severity vulnerability in TP-Link Systems Inc. TL-WL841N v13, published on 23 Apr 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
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.
Weakness: CWE-1394
Which versions are affected by CVE-2026-5039?
It affects 1 product.
Products include Tp-Link Tl-Wr841n Firmware.
How do I fix CVE-2026-5039?
No fix has been published for CVE-2026-5039 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-5039 being exploited?
There is no known exploitation of CVE-2026-5039 in the wild and no public exploit code.
Other vulnerabilities in TP-Link Systems Inc. TL-WL841N v13
Sources
Also known as GHSA-f7mq-68q8-xqv6.