Zbtlink WRC1 infosrvd service command injection

Summaryinfo

A vulnerability was found in Zbtlink WE1326, WE2426-C, WE357, WE5926, WE5926-EC_QP, WE5926-WD, WE826-Q, WE826-T2, WE826-WD, WF3526-P, WG108, WG3526, CTN720-W1, LF-1541, MT7620N and WRC1 and classified as very critical. Impacted is an unknown function of the component infosrvd service. Executing a manipulation can lead to command injection. This vulnerability appears as CVE-2026-74233. The attack may be performed from remote. There is no available exploit.

Detailsinfo

A vulnerability has been found in Zbtlink WE1326, WE2426-C, WE357, WE5926, WE5926-EC_QP, WE5926-WD, WE826-Q, WE826-T2, WE826-WD, WF3526-P, WG108, WG3526, CTN720-W1, LF-1541, MT7620N and WRC1 and classified as very critical. This vulnerability affects an unknown code of the component infosrvd service. The manipulation with an unknown input leads to a command injection vulnerability. The CWE definition for the vulnerability is CWE-77. The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when it is sent to a downstream component. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

Zbtlink WE1326, WE357, WE5926, WE5926-WD, WE826-Q, WE826-T2, WE826-WD, WG108, and WG3526 firmware 19.1101, Zbtlink WE2426-C firmware 19.1112, Zbtlink WE5926-EC_QP firmware 20.0516, Zbtlink WF3526-P firmware 19.051, CTN720-W1, LF-1541, and MT7620N firmware 19.1101, and WRC1 firmware 20.0622 contain an unauthenticated command injection in the infosrvd service (UDP/9992). A remote unauthenticated attacker can send a crafted UDP packet to execute arbitrary commands as root. The service's authentication uses a hardcoded salt and an all-zero wildcard MAC bypass, rendering it ineffective.

The advisory is shared for download at vulncheck.com. This vulnerability was named CVE-2026-74233 since 08/14/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 08/27/2026). The MITRE ATT&CK project declares the attack technique as T1202.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

• Zbtlink

Name

• CTN720-W1
• LF-1541
• MT7620N
• WE357
• WE826-Q
• WE826-T2
• WE826-WD
• WE1326
• WE2426-C
• WE5926
• WE5926-EC_QP
• WE5926-WD
• WF3526-P
• WG108
• WG3526
• WRC1

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Once again VulDB remains the best source for vulnerability data.

Discussion