How severe is CVE-2021-3125?

CVE-2021-3125 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-3125 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (71st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3125?

CVE-2021-3125 primarily affects Tp-link Tl-xdr3230 Firmware. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-3125?

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.

When was CVE-2021-3125 published?

CVE-2021-3125 was published on 2021-04-12 and last updated on 2026-06-17.

CVE-2021-3125

CVE-2021-3125 is a high-severity vulnerability in Tp-link Tl-xdr3230 Firmware with a CVSS 3.x base score of 7.5. 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-834.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 4.3
EPSS exploit prediction: 2% (71st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-834
Affected product: Tp-link Tl-xdr3230 Firmware
Published: 2021-04-12
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2021-3125?: 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.
How severe is CVE-2021-3125?: CVE-2021-3125 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-3125 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (71st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3125?: CVE-2021-3125 primarily affects Tp-link Tl-xdr3230 Firmware. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-3125?: 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.
When was CVE-2021-3125 published?: CVE-2021-3125 was published on 2021-04-12 and last updated on 2026-06-17.

References

Affected products (6)

cpe:2.3:o:tp-link:tl-xdr3230_firmware:*:*:*:*:*:easy_exhibition_turbo:*:*
cpe:2.3:o:tp-link:tl-xdr5430_firmware:*:*:*:*:*:easy_exhibition:*:*
cpe:2.3:o:tp-link:tl-xdr3250_firmware:*:*:*:*:*:easy_exhibition:*:*
cpe:2.3:o:tp-link:tl-xdr1860_firmware:*:*:*:*:*:easy_exhibition:*:*
cpe:2.3:o:tp-link:tl-xdr1850_firmware:*:*:*:*:*:easy_exhibition:*:*
cpe:2.3:o:tp-link:tl-xdr6060_firmware:*:*:*:*:*:easy_exhibition:*:*

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