Unauthenticated command execution via telnet setting injection
Published Apr 27, 2026 · Updated Apr 27, 2026
OS command injection in TOTOLINK A8000RU 7.1cu.643_b20200521 allows remote attackers to execute arbitrary commands via a crafted CGI request. The setTelnetCfg handler inserts the telnet_enabled value into a command buffer with snprintf and passes it to CsteSystem, which invokes execv without neutralizing shell syntax. No authentication or user interaction is required, and successful requests execute commands with the web service's device privileges.
Summary
What happened
OS command injection in TOTOLINK A8000RU 7.1cu.643_b20200521 allows remote attackers to execute arbitrary commands via a crafted CGI request. The setTelnetCfg handler inserts the telnet_enabled value into a command buffer with snprintf and passes it to CsteSystem, which invokes execv without neutralizing shell syntax. No authentication or user interaction is required, and successful requests execute commands with the web service's device privileges.
The record
- CVE
- CVE-2026-7152
- Published
- Apr 27, 2026
- Updated
- Apr 27, 2026
- Vendor
- TOTOLINK
- Product
- A8000RU
- Classifications
- CWE-78, CWE-77, T1059.004, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 27, 2026CVE publishedPublication date reported by the CVE source.
- Apr 27, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=7.1cu.643_b20200521
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- A8000RU setTelnetCfg command-injection proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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