HOMEVULNERABILITIESCVE-2021-3125
HIGH

CVE-2021-3125

CWE-834Published: April 12, 2021· Updated: Jun 17, 2026

7.5
CVSS v3.1

Official Description

In TP-Link TL-XDR3230 < 1.0.12, TL-XDR1850 < 1.0.9, TL-XDR1860 < 1.0.14, TL-XDR3250 < 1.0.2, TL-XDR6060 Turbo < 1.1.8, TL-XDR5430 < 1.0.11, and possibly others, when IPv6 is used, a routing loop can occur that generates excessive network traffic between an affected device and its upstream ISP's router. This occurs when a link prefix route points to a point-to-point link, a destination IPv6 address belongs to the prefix and is not a local IPv6 address, and a router advertisement is received with at least one global unique IPv6 prefix for which the on-link flag is set.

NVD Source

Technical Analysis

CVE-2021-3125 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

A successful exploit results in availability disruption (denial of service), with a CVSS base score of 7.5.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.None
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityNone
IntegrityNone
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected Vendors & Products

tp-link12 product(s)
tl-xdr3230 firmwaretl-xdr3230tl-xdr5430 firmwaretl-xdr5430tl-xdr3250 firmwaretl-xdr3250tl-xdr1860 firmwaretl-xdr1860tl-xdr1850 firmwaretl-xdr1850tl-xdr6060 firmwaretl-xdr6060
Source: NVD CPE · 12 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
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Official Patches & Advisories

All References (12)

Quick Facts

CVE IDCVE-2021-3125
CVSS Score7.5 / 10
SeverityHIGH
WeaknessCWE-834
CISA KEVNo
Affected1 vendor(s)
PublishedApr 12, 2021

Related CVEs (CWE-834)

Recommended Actions

  • Apply vendor patches immediately
  • Monitor CVE-2021-3125 in threat intel feeds
  • Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.