CVE-2026-5039
Predictable Default Cryptographic Key Used for DES Encryption in TP-Link TL-WL841N
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.
Attack profile
How easy it is to exploit
- Attack vector
- Adjacent network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Predictable Default Cryptographic Key Used for DES Encryption in TP-Link TL-WL841N
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.
- Record
CVE-2026-5039- CVSS 4.0
- 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 - Weakness
- CWE-1394
- Updated
- 2026-11-02
EUVDEUVD-2026-25250
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.
- Record
EUVD-2026-25250- CVSS 4.0
- 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 - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-f7mq-68q8-xqv6
TP-Link TL-WR841N v13 uses DES-CBC encryption in the TDDPv2 debug protocol with a cryptographic...
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.
- Record
GHSA-f7mq-68q8-xqv6- CVSS 4.0
- 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/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 - CVSS 3.1
- 8.8 High
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-1394
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-5039- CVSS 4.0
- 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/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 - CVSS 3.1
- 8.8 High
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-1394
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-5039 is a medium vulnerability (CVSS 6.1) in Tp-link Tl-wr841n Firmware, published April 23, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.13%, the 2nd percentile. No source names a fixed version.