CVE-2026-3841
CVE-2026-3841 is a high-severity vulnerability in Tp-link Tl-mr6400 Firmware with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-78.
Key facts
- Severity: High (CVSS 3.x base score 8.8)
- CVSS v4: 8.5
- EPSS exploit prediction: 2% (76th percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-11655
- Weakness: CWE-78
- Affected product: Tp-link Tl-mr6400 Firmware
- Published:
- Last modified:
Description
A command injection vulnerability has been identified in the Telnet command-line interface (CLI) of TP-Link TL-MR6400 v5.3. This issue is caused by insufficient sanitization of data processed during specific CLI operations. An authenticated attacker with elevated privileges may be able to execute arbitrary system commands. Successful exploitation may lead to full device compromise, including potential loss of confidentiality, integrity, and availability.
Frequently asked questions
- What is CVE-2026-3841?
- A command injection vulnerability has been identified in the Telnet command-line interface (CLI) of TP-Link TL-MR6400 v5.3. This issue is caused by insufficient sanitization of data processed during specific CLI operations. An authenticated attacker with elevated privileges may be able to execute arbitrary system commands. Successful exploitation may lead to full device compromise, including potential loss of confidentiality, integrity, and availability.
- How severe is CVE-2026-3841?
- CVE-2026-3841 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2026-3841 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2026-3841?
- CVE-2026-3841 affects Tp-link Tl-mr6400 Firmware. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2026-3841?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- Does CVE-2026-3841 have an EU (EUVD) identifier?
- Yes. CVE-2026-3841 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-11655.
- When was CVE-2026-3841 published?
- CVE-2026-3841 was published on 2026-03-12 and last updated on 2026-06-17.
References
- https://www.tp-link.com/en/support/download/tl-mr6400/v5.30/#Firmware
- https://www.tp-link.com/us/support/faq/5016/
Affected products (1)
- cpe:2.3:o:tp-link:tl-mr6400_firmware:*:*:*:*:*:*:*:*
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