How severe is CVE-2021-20709?

CVE-2021-20709 has a CVSS 3.x base score of 7.2, rated high severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-20709 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (47th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-20709?

CVE-2021-20709 primarily affects Nec Aterm Wf1200cr Firmware. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-20709?

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-2021-20709 published?

CVE-2021-20709 was published on 2021-04-26 and last updated on 2026-06-17.

CVE-2021-20709

CVE-2021-20709 is a high-severity vulnerability in Nec Aterm Wf1200cr Firmware with a CVSS 3.x base score of 7.2. 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-354.

Key facts

Severity: High (CVSS 3.x base score 7.2)
CVSS v2: 9.0
EPSS exploit prediction: 1% (47th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-354
Affected product: Nec Aterm Wf1200cr Firmware
Published: 2021-04-26
Last modified: 2026-06-17

Description

Improper validation of integrity check value vulnerability in NEC Aterm WF1200CR firmware Ver1.3.2 and earlier, Aterm WG1200CR firmware Ver1.3.3 and earlier, and Aterm WG2600HS firmware Ver1.5.1 and earlier allows an attacker with an administrative privilege to execute arbitrary OS commands by sending a specially crafted request to a specific URL.

Frequently asked questions

What is CVE-2021-20709?: Improper validation of integrity check value vulnerability in NEC Aterm WF1200CR firmware Ver1.3.2 and earlier, Aterm WG1200CR firmware Ver1.3.3 and earlier, and Aterm WG2600HS firmware Ver1.5.1 and earlier allows an attacker with an administrative privilege to execute arbitrary OS commands by sending a specially crafted request to a specific URL.
How severe is CVE-2021-20709?: CVE-2021-20709 has a CVSS 3.x base score of 7.2, rated high severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-20709 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (47th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-20709?: CVE-2021-20709 primarily affects Nec Aterm Wf1200cr Firmware. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-20709?: 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-2021-20709 published?: CVE-2021-20709 was published on 2021-04-26 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:o:nec:aterm_wf1200cr_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:nec:aterm_wg1200cr_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:nec:aterm_wg2600hs_firmware:*:*:*:*:*:*:*:*

More vulnerabilities in Nec Aterm Wf1200cr Firmware

CVE-2026-4622 — Critical (CVSS 9.8): OS Command Injection vulnerability in NEC Platforms, Ltd. Aterm Series allows a attacker to execute arbitrary OS…
CVE-2018-16195 — High (CVSS 8.8): Aterm WF1200CR and Aterm WG1200CR (Aterm WF1200CR firmware Ver1.1.1 and earlier, Aterm WG1200CR firmware Ver1.0.1 and…
CVE-2021-20708 — High (CVSS 7.2): NEC Aterm devices (Aterm WF1200CR firmware Ver1.3.2 and earlier, Aterm WG1200CR firmware Ver1.3.3 and earlier, and…
CVE-2018-16194 — High (CVSS 7.2): Aterm WF1200CR and Aterm WG1200CR (Aterm WF1200CR firmware Ver1.1.1 and earlier, Aterm WG1200CR firmware Ver1.0.1 and…
CVE-2026-4309 — Medium (CVSS 6.5): Missing Authorization vulnerability in NEC Platforms, Ltd. Aterm Series allows a attacker to get a specific device…
CVE-2018-16192 — Medium (CVSS 6.5): Aterm WF1200CR and Aterm WG1200CR (Aterm WF1200CR firmware Ver1.1.1 and earlier, Aterm WG1200CR firmware Ver1.0.1 and…

All CVEs affecting Nec Aterm Wf1200cr Firmware →

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