How severe is CVE-2025-8940?

CVE-2025-8940 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-2025-8940 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-8940?

CVE-2025-8940 affects Tenda Ac20 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-8940?

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-2025-8940 have an EU (EUVD) identifier?

Yes. CVE-2025-8940 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-24670.

When was CVE-2025-8940 published?

CVE-2025-8940 was published on 2025-08-14 and last updated on 2026-06-17.

CVE-2025-8940

CVE-2025-8940 is a high-severity vulnerability in Tenda Ac20 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% (51st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-24670
Weakness: CWE-119
Affected product: Tenda Ac20 Firmware
Published: 2025-08-14
Last modified: 2026-06-17

Description

A vulnerability was identified in Tenda AC20 up to 16.03.08.12. Affected by this vulnerability is the function strcpy of the file /goform/saveParentControlInfo. The manipulation of the argument Time leads to buffer overflow. The attack can be launched remotely. The exploit has been disclosed to the public and may be used.

Frequently asked questions

What is CVE-2025-8940?: A vulnerability was identified in Tenda AC20 up to 16.03.08.12. Affected by this vulnerability is the function strcpy of the file /goform/saveParentControlInfo. The manipulation of the argument Time leads to buffer overflow. The attack can be launched remotely. The exploit has been disclosed to the public and may be used.
How severe is CVE-2025-8940?: CVE-2025-8940 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-2025-8940 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-8940?: CVE-2025-8940 affects Tenda Ac20 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-8940?: 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-2025-8940 have an EU (EUVD) identifier?: Yes. CVE-2025-8940 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-24670.
When was CVE-2025-8940 published?: CVE-2025-8940 was published on 2025-08-14 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:tenda:ac20_firmware:*:*:*:*:*:*:*:*

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