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CVE-2026-0711 Zyxel CVE debrief

CVE-2026-0711 is a post-authentication command injection vulnerability in the EasyMesh-related APIs of Zyxel DX3300-T0 firmware versions through 5.50(ABVY.7.1)C0. An authenticated, adjacent attacker with administrator privileges could exploit this vulnerability to execute OS commands on an affected device. The vulnerability exists due to insufficient input validation in the EasyMesh-related APIs, allowing an attacker to inject malicious OS commands. This type of vulnerability can lead to unauthorized access, data breaches, or disruption of services. Administrators and users of Zyxel DX3300-T0 devices should be aware of this vulnerability and take necessary actions to mitigate the risk.

Vendor
Zyxel
Product
DX3300‑T0
CVSS
MEDIUM 6.8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-04-28
Original CVE updated
2026-07-25
Advisory published
2026-04-28
Advisory updated
2026-07-25

Who should care

Administrators and users of Zyxel DX3300-T0 devices should be aware of this vulnerability and take necessary actions to mitigate the risk. This includes applying the vendor-provided patch or updating to a version that addresses this vulnerability, restricting access to the EasyMesh-related APIs to only trusted users and networks, and monitoring for suspicious activity. Additionally, security teams should review compensating controls for exposed systems while remediation is scheduled and verified.

Technical summary

The vulnerability exists in the EasyMesh-related APIs of Zyxel DX3300-T0 firmware versions through 5.50(ABVY.7.1)C0. An attacker with post-authentication and administrator privileges can inject OS commands. The CVSS score is 6.8, indicating a medium severity. The vulnerability is caused by insufficient input validation, allowing an attacker to inject malicious OS commands. To exploit this vulnerability, an attacker must have adjacent access and administrator privileges. The vulnerability can be mitigated by applying the vendor-provided patch or updating to a version that addresses this vulnerability.

Defensive priority

Medium priority due to the requirement for authentication and adjacent access. However, given the potential impact of the vulnerability, it is essential to address it promptly and thoroughly.

Recommended defensive actions

  • Apply the vendor-provided patch or update to a version that addresses this vulnerability.
  • Restrict access to the EasyMesh-related APIs to only trusted users and networks.
  • Monitor for suspicious activity and implement logging and auditing to detect potential exploitation attempts.
  • Review compensating controls for exposed systems while remediation is scheduled and verified.
  • Check relevant monitoring, detection, and logs for exposed assets that need extra review.
  • Track exceptions, retest remediated assets, and close the item only after evidence is documented.
  • Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.

Evidence notes

The CVE record and NVD detail provide information on the vulnerability, its impact, and potential mitigations. A vendor advisory is available for further guidance. Evidence is limited to public sources and may not reflect the full scope or current accuracy of the vulnerability. Defenders should verify the affected product deployments, review official advisories, and plan for vendor-supported updates or mitigations.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-0711 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-0711

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-0711 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-0711

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

  • Mitigation or vendor reference

    Unverified legacy reference

    URL: https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-command-injection-vulnerabilities-in-certain-4g-lte-5g-nr-cpe-dsl-ethernet-cpe-fiber-onts-and-wireless-extenders-04-28-2026

    [email protected] - Vendor Advisory

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.