WAVLINK WN553X1-B: OS command injection in WireGuard CLI group handler
Summary
The WAVLINK WN553X1-B router with firmware V260403_2.0.0 contains an OS command injection in the WireGuard CLI group handler (function sub_41A748 in /bin/ioos). The group_id and group_name parameters are inserted unchecked into shell commands. An attacker with a valid session can run arbitrary commands as root on the device, which can lead to full compromise. A public exploit has been published and no vendor fix is known.
Affected
- WAVLINK WN553X1-B (model WN553X3B according to the researcher), firmware V260403_2.0.0
Fixed in
Unknown.
Workaround
- No official mitigation known.
- Disable remote administration and do not expose the web interface to the internet.
- Restrict access to the management interface to trusted hosts and networks.
- Change the default admin password.
Exploitation
- Public exploit: yes, according to VulDB.
- Exploitation in the wild: Unknown.
- A valid session token is required. The researcher states that the factory default password admin, if unchanged, allows one to be obtained.
Our recommendation
- Inventory all WAVLINK WN553X1-B devices and check their firmware versions.
- Remove any remote administration access from the internet.
- Change default credentials immediately.
- Monitor the vendor for a fixed firmware and apply it promptly.
- Consider replacing the device if no fix is available.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- VulDB entry CVE-2026-120240 vuldb.com
- VulDB CVE record CVE-2026-120240 vuldb.com
- Researcher write-up (HACKALL) on wireguard_cli_group command injection github.com
- OffSeq Radar entry CVE-2026-120240 radar.offseq.com
- Researcher IOT-CVE overview for WAVLINK WN553X1-B github.com
- TheHackerWire: related WAVLINK WN553X1-B command injection advisory www.thehackerwire.com
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 1 Nov 2026, 20:20.
Original description (NVD)
A vulnerability was determined in WAVLINK WN553X1-B V260403_2.0.0. This issue affects the function sub_41A748 of the file /bin/ioos of the component WireGuard CLI Group Handler. Executing a manipulation of the argument group_id/group_name can lead to os command injection. The attack may be performed from remote. The exploit has been publicly disclosed and may be utilized. The vendor was contacted early about this disclosure.
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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