How severe is CVE-2021-34236?

CVE-2021-34236 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-2021-34236 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-34236?

CVE-2021-34236 affects Netgear R8000 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-34236?

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-2021-34236 published?

CVE-2021-34236 was published on 2022-09-08 and last updated on 2026-06-17.

CVE-2021-34236

CVE-2021-34236 is a critical-severity vulnerability in Netgear R8000 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-120.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 1% (64th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-120
Affected product: Netgear R8000 Firmware
Published: 2022-09-08
Last modified: 2026-06-17

Description

Buffer Overflow in Netgear R8000 Router with firmware v1.0.4.56 allows remote attackers to execute arbitrary code or cause a denial-of-service by sending a crafted POST to '/bd_genie_create_account.cgi' with a sufficiently long parameter 'register_country'.

Frequently asked questions

What is CVE-2021-34236?: Buffer Overflow in Netgear R8000 Router with firmware v1.0.4.56 allows remote attackers to execute arbitrary code or cause a denial-of-service by sending a crafted POST to '/bd_genie_create_account.cgi' with a sufficiently long parameter 'register_country'.
How severe is CVE-2021-34236?: CVE-2021-34236 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-2021-34236 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-34236?: CVE-2021-34236 affects Netgear R8000 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-34236?: 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-2021-34236 published?: CVE-2021-34236 was published on 2022-09-08 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:netgear:r8000_firmware:1.0.4.56:*:*:*:*:*:*:*

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