How severe is CVE-2021-27246?

CVE-2021-27246 has a CVSS 3.x base score of 8.0, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-27246 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 7% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-27246?

CVE-2021-27246 affects Tp-link Ac1750 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-27246?

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-2021-27246 published?

CVE-2021-27246 was published on 2021-04-14 and last updated on 2026-06-17.

CVE-2021-27246

CVE-2021-27246 is a high-severity vulnerability in Tp-link Ac1750 Firmware with a CVSS 3.x base score of 8.0. 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-121.

Key facts

Severity: High (CVSS 3.x base score 8.0)
CVSS v2: 7.9
EPSS exploit prediction: 7% (93rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-121
Affected product: Tp-link Ac1750 Firmware
Published: 2021-04-14
Last modified: 2026-06-17

Description

This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of TP-Link Archer A7 AC1750 1.0.15 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the handling of MAC addresses by the tdpServer endpoint. A crafted TCP message can write stack pointers to the stack. An attacker can leverage this vulnerability to execute code in the context of the root user. Was ZDI-CAN-12306.

Frequently asked questions

What is CVE-2021-27246?: This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of TP-Link Archer A7 AC1750 1.0.15 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the handling of MAC addresses by the tdpServer endpoint. A crafted TCP message can write stack pointers to the stack. An attacker can leverage this vulnerability to execute code in the context of the root user. Was ZDI-CAN-12306.
How severe is CVE-2021-27246?: CVE-2021-27246 has a CVSS 3.x base score of 8.0, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-27246 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 7% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-27246?: CVE-2021-27246 affects Tp-link Ac1750 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-27246?: 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-2021-27246 published?: CVE-2021-27246 was published on 2021-04-14 and last updated on 2026-06-17.

References

https://www.zerodayinitiative.com/advisories/ZDI-21-215/

Affected products (1)

cpe:2.3:o:tp-link:ac1750_firmware:1.0.15:*:*:*:*:*:*:*

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