How severe is CVE-2021-35003?

CVE-2021-35003 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-35003 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 8% (94th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-35003?

CVE-2021-35003 affects Tp-link Archer C90 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-35003?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2021-35003 published?

CVE-2021-35003 was published on 2022-01-21 and last updated on 2026-06-17.

CVE-2021-35003

CVE-2021-35003 is a critical-severity vulnerability in Tp-link Archer C90 Firmware with a CVSS 3.x base score of 9.8. 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-121.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 10.0
EPSS exploit prediction: 8% (94th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-121
Affected product: Tp-link Archer C90 Firmware
Published: 2022-01-21
Last modified: 2026-06-17

Description

This vulnerability allows remote attackers to execute arbitrary code on affected installations of TP-Link Archer C90 1.0.6 Build 20200114 rel.73164(5553) routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the handling of DNS responses. A crafted DNS message can trigger an overflow of a fixed-length, stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-14655.

Frequently asked questions

What is CVE-2021-35003?: This vulnerability allows remote attackers to execute arbitrary code on affected installations of TP-Link Archer C90 1.0.6 Build 20200114 rel.73164(5553) routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the handling of DNS responses. A crafted DNS message can trigger an overflow of a fixed-length, stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-14655.
How severe is CVE-2021-35003?: CVE-2021-35003 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-35003 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 8% (94th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-35003?: CVE-2021-35003 affects Tp-link Archer C90 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-35003?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-35003 published?: CVE-2021-35003 was published on 2022-01-21 and last updated on 2026-06-17.

References

https://www.zerodayinitiative.com/advisories/ZDI-22-080/

Affected products (1)

cpe:2.3:o:tp-link:archer_c90_firmware:1.0.6:build_20200114:*:*:*:*:*:*

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