Critical Command Injection Flaws Expose Totolink A7100RU and A8000RU Routers
Two Totolink router models, A7100RU and A8000RU, were disclosed with critical OS command injection vulnerabilities in the CGI handler endpoint /cgi-bin/cstecgi.cgi. The flaws affect the setVpnPassCfg function and stem from improper handling of the pptpPassThru argument, allowing attackers to inject operating system commands remotely. The issues were assigned CVE-2026-5850 for the A7100RU running firmware 7.4cu.2313_b20191024 and CVE-2026-7037 for the A8000RU running firmware 7.1cu.643_b20200521.
Both vulnerabilities are classified under CWE-78 and CWE-77, and were reported as remotely exploitable without privileges or user interaction. The disclosures indicate that public exploits are available, materially raising the risk of opportunistic compromise of exposed devices. Severity scoring across CVSS v2, CVSS v3.1, and CVSS v4.0 places the flaws at critical or maximum-impact levels, making internet-facing Totolink routers running the affected firmware high-priority targets for remediation or isolation.
Get ahead of threats like this
Mallory correlates global threat intelligence with your attack surface — know if you’re exposed before adversaries strike.
How this story unfolded
4 events from the most recent confirmed update back to the earliest known activity.
Public exploit noted for CVE-2026-7037
The CVE-2026-7037 entry stated that a public exploit had been released for the Totolink A8000RU vulnerability, increasing the likelihood of real-world attacks.
CVE-2026-7037 disclosed for Totolink A8000RU command injection
A CVE entry was recorded for a remote OS command injection vulnerability in Totolink A8000RU firmware 7.1cu.643_b20200521. The flaw affects the setVpnPassCfg function in /cgi-bin/cstecgi.cgi through the pptpPassThru argument and was classified as remotely exploitable.
Public exploit noted for CVE-2026-5850
The CVE-2026-5850 record indicated that a public exploit was available for the Totolink A7100RU command injection vulnerability, raising the risk of exploitation.
CVE-2026-5850 disclosed for Totolink A7100RU command injection
A CVE entry for a remote OS command injection flaw in Totolink A7100RU firmware 7.4cu.2313_b20191024 was received by VulDB. The issue affects the setVpnPassCfg function in /cgi-bin/cstecgi.cgi via the pptpPassThru argument and was reported as remotely exploitable without privileges or user interaction.
Related entities
Vulnerabilities, threat actors, malware, products, organizations, and breaches Mallory has linked to this story.
Sources
2 references tracked. Mallory keeps watching after this page renders.
See the full picture, correlated to your attack surface.
Map indicators from this story to your assets and identify affected systems in minutes.
Every observed campaign, victim, and pivot linked to actors named in this story.
Malware, exploits, and IOCs connected to the activity described here.
YARA, Sigma, and Snort rules deployed to your SIEM as soon as they’re published.
Get matching new stories delivered to your team as they break — not the next morning.
Ask questions about this story and take action on the answers.
Related stories
Other stories Mallory is tracking that overlap on entities, sources, or topic labels.
Critical Command Injection Flaws Expose Totolink A8000RU Routers to Remote RCE
Three critical vulnerabilities, **CVE-2026-7121**, **CVE-2026-7122**, and **CVE-2026-7125**, were disclosed in the **Totolink A8000RU** router running firmware `7.1cu.643_b20200521`, all affecting the `/cgi-bin/cstecgi.cgi` CGI handler. The flaws are OS command injection issues in the `setWizardCfg`, `setUPnPCfg`, and `setWiFiEasyCfg` functions, where crafted input to the `wizard`, `enable`, and `merge` arguments can trigger command execution on the device. The vulnerabilities are mapped to **CWE-78** and **CWE-77** and were rated critical across **CVSS v2**, **CVSS v3.1**, and **CVSS v4.0** scoring schemes. All three issues are remotely exploitable over the network and require **no privileges** and **no user interaction**, creating a high-risk exposure for internet-accessible devices. Public exploit information has already been disclosed, with references including VulDB entries and a GitHub proof-of-concept, increasing the likelihood of near-term exploitation. The disclosures indicate that multiple administrative configuration paths in the router's web interface can be abused for remote code execution, making unpatched A8000RU systems a priority for immediate review and remediation.
Apr 28, 2026
Publicly Exploitable Command Injection Flaws Disclosed in Totolink A3300R Router
Two high-severity command injection vulnerabilities have been disclosed in the **Totolink A3300R** router, both affecting firmware version `17.0.0cu.557_b20221024` and exposing the device to remote code execution through `/cgi-bin/cstecgi.cgi`. The flaws are tracked as **`CVE-2026-5104`** and **`CVE-2026-5101`**. `CVE-2026-5104` affects the `setStaticRoute` function, where manipulation of the `ip` argument can trigger command injection, while `CVE-2026-5101` affects the `setLanCfg` function in the Parameter Handler component through the `lanIp` argument. Public exploit material has been disclosed for both issues, according to VulDB and referenced advisory material, raising the risk of active abuse against exposed devices. NVD subsequently added initial analysis for the CVEs, assigning higher **CVSS v3.1** severity assessments than the original CNA submissions and mapping the weaknesses to **`CWE-77`**, **`CWE-74`**, and **`CWE-78`**. The disclosures indicate that attackers could remotely inject operating system commands via crafted requests, making patching, exposure reduction, and monitoring of internet-facing Totolink A3300R systems urgent priorities.
Apr 23, 2026
Unauthenticated Command Injection Flaws Disclosed in Totolink A7100RU Router
Two critical vulnerabilities, **CVE-2026-5851** and **CVE-2026-5976**, were disclosed in the **Totolink A7100RU** router running firmware `7.4cu.2313_b20191024`, exposing the device to remote **OS command injection** without authentication or user interaction. Both flaws affect `/cgi-bin/cstecgi.cgi` in the router's CGI handler: CVE-2026-5851 is tied to the `setUPnPCfg` function through the `enable` argument, while CVE-2026-5976 affects the `setStorageCfg` function through the `sambaEnabled` argument. The vulnerabilities were classified under **CWE-78** and **CWE-77** and were assigned high to critical severity across CVSS versions, reflecting potential compromise of confidentiality, integrity, and availability. Public exploit information has reportedly been released, including references to **VulDB** and a **GitHub** disclosure repository, increasing the likelihood of exploitation against exposed devices that have not been updated or otherwise mitigated.
Apr 13, 2026