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CVE-2026-3227 TP-Link CVE debrief

CVE-2026-3227 is a high-severity command injection vulnerability affecting TP-Link TL-WR802N v4, TL-WR841N v14, and TL-WR840N v6 routers. The vulnerability allows an authenticated attacker to upload a crafted configuration file, leading to the execution of OS commands with root privileges during port-trigger processing. Successful exploitation enables an attacker to execute system commands with root privileges, resulting in full device compromise. The vulnerability has a CVSS score of 8.5 and is considered HIGH severity. The CVE was published on March 16, 2026, and last modified on July 1, 2026.

Vendor
TP-Link
Product
TL-WR802N v4, TL-WR841N v14, TL-WR840N v6
CVSS
HIGH 8.5
CISA KEV
Not listed in stored evidence
Original CVE published
2026-03-16
Original CVE updated
2026-07-01
Advisory published
2026-03-16
Advisory updated
2026-07-01

Who should care

Administrators and users of TP-Link TL-WR802N v4, TL-WR841N v14, and TL-WR840N v6 routers should be aware of this vulnerability and take immediate action to mitigate the risk. This vulnerability can be exploited by an authenticated attacker, which makes it particularly concerning for organizations that have these devices in their network. Security teams should prioritize patching or updating affected devices to prevent potential attacks.

Technical summary

The command injection vulnerability in TP-Link routers is caused by improper neutralization of special elements used in an OS command. The vulnerability exists in the router configuration import function, which allows an authenticated attacker to upload a crafted configuration file. This file can be designed to execute OS commands with root privileges during port-trigger processing. The vulnerability has been assigned a CVSS score of 8.5, indicating high severity. The affected devices are TL-WR802N v4, TL-WR841N v14, and TL-WR840N v6.

Defensive priority

High priority should be given to patching or updating affected TP-Link devices. Security teams should ensure that all TL-WR802N v4, TL-WR841N v14, and TL-WR840N v6 routers are updated with the latest firmware to prevent exploitation of this vulnerability.

Recommended defensive actions

  • Update TL-WR802N v4 to the latest firmware version.
  • Update TL-WR841N v14 to the latest firmware version.
  • Update TL-WR840N v6 to the latest firmware version.
  • Restrict access to the router configuration import function.
  • Monitor network activity for suspicious commands.

Evidence notes

The CVE-2026-3227 vulnerability was identified in TP-Link routers and has been documented in the official CVE record and NVD detail pages. The vulnerability allows an authenticated attacker to execute system commands with root privileges, leading to full device compromise. The affected devices and CVSS score have been confirmed through official sources.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-3227 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-3227

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

  • CVE-2026-3227 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-3227

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

Supplemental references

  • Source reference

    Unverified legacy reference

    URL: https://www.tp-link.com/en/support/download/tl-wr802n/v4/

    f23511db-6c3e-4e32-a477-6aa17d310630 - Product

  • Source reference

    Unverified legacy reference

    URL: https://www.tp-link.com/en/support/download/tl-wr840n/v6/

    f23511db-6c3e-4e32-a477-6aa17d310630 - Product

  • Source reference

    Unverified legacy reference

    URL: https://www.tp-link.com/en/support/download/tl-wr841n/v14/

    f23511db-6c3e-4e32-a477-6aa17d310630 - Product

  • Source reference

    Unverified legacy reference

    URL: https://www.tp-link.com/us/support/download/tl-wr802n/v4/

    f23511db-6c3e-4e32-a477-6aa17d310630 - Product

  • Source reference

    Unverified legacy reference

    URL: https://www.tp-link.com/us/support/download/tl-wr841n/v14/

    f23511db-6c3e-4e32-a477-6aa17d310630 - Product

  • Mitigation or vendor reference

    Unverified legacy reference

    URL: https://www.tp-link.com/us/support/faq/5018/

    f23511db-6c3e-4e32-a477-6aa17d310630 - 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.