CVE-2026-5039
Predictable Default Cryptographic Key Used for DES Encryption in TP-Link TL-WL841N
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.
INFO
Published Date :
April 23, 2026, 6:16 p.m.
Last Modified :
April 23, 2026, 6:16 p.m.
Remotely Exploit :
No
Source :
f23511db-6c3e-4e32-a477-6aa17d310630
Affected Products
The following products are affected by CVE-2026-5039
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 4.0 | MEDIUM | f23511db-6c3e-4e32-a477-6aa17d310630 | ||||
| CVSS 4.0 | MEDIUM | f23511db-6c3e-4e32-a477-6aa17d310630 |
Solution
- Change default web management credentials immediately.
- Disable the TDDPv2 debug protocol if not in use.
- Apply firmware updates when available from the vendor.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-5039.
| URL | Resource |
|---|---|
| https://www.tp-link.com/us/support/download/tl-wr841n/v13/#Firmware |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-5039 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-5039
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-5039 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-5039 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by f23511db-6c3e-4e32-a477-6aa17d310630
Apr. 23, 2026
Action Type Old Value New Value Added 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. Added CVSS V4.0 AV:A/AC:L/AT:P/PR:N/UI:N/VC:L/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-1394 Added Reference https://www.tp-link.com/us/support/download/tl-wr841n/v13/#Firmware