How severe is CVE-2026-2870?

CVE-2026-2870 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-2870 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-2870?

CVE-2026-2870 affects Tenda A21 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-2870?

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.

Does CVE-2026-2870 have an EU (EUVD) identifier?

Yes. CVE-2026-2870 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-7519.

When was CVE-2026-2870 published?

CVE-2026-2870 was published on 2026-02-21 and last updated on 2026-06-17.

CVE-2026-2870

CVE-2026-2870 is a high-severity vulnerability in Tenda A21 Firmware with a CVSS 3.x base score of 8.8. 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-119.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 9.0
CVSS v4: 7.4
EPSS exploit prediction: 1% (44th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-7519
Weakness: CWE-119
Affected product: Tenda A21 Firmware
Published: 2026-02-21
Last modified: 2026-06-17

Description

A security flaw has been discovered in Tenda A21 1.0.0.0. Affected by this issue is the function set_qosMib_list of the file /goform/formSetQosBand. The manipulation of the argument list results in stack-based buffer overflow. The attack can be executed remotely. The exploit has been released to the public and may be used for attacks.

Frequently asked questions

What is CVE-2026-2870?: A security flaw has been discovered in Tenda A21 1.0.0.0. Affected by this issue is the function set_qosMib_list of the file /goform/formSetQosBand. The manipulation of the argument list results in stack-based buffer overflow. The attack can be executed remotely. The exploit has been released to the public and may be used for attacks.
How severe is CVE-2026-2870?: CVE-2026-2870 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-2870 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-2870?: CVE-2026-2870 affects Tenda A21 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-2870?: 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.
Does CVE-2026-2870 have an EU (EUVD) identifier?: Yes. CVE-2026-2870 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-7519.
When was CVE-2026-2870 published?: CVE-2026-2870 was published on 2026-02-21 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:tenda:a21_firmware:1.0.0.0:*:*:*:*:*:*:*

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