How severe is CVE-2025-28020?

CVE-2025-28020 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2025-28020 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (25th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-28020?

CVE-2025-28020 affects Totolink A800r Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-28020?

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-2025-28020 have an EU (EUVD) identifier?

Yes. CVE-2025-28020 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-12101.

When was CVE-2025-28020 published?

CVE-2025-28020 was published on 2025-04-23 and last updated on 2026-06-17.

CVE-2025-28020

CVE-2025-28020 is a high-severity vulnerability in Totolink A800r Firmware with a CVSS 3.x base score of 7.3. 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: High (CVSS 3.x base score 7.3)
EPSS exploit prediction: 0% (25th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-12101
Weakness: CWE-120
Affected product: Totolink A800r Firmware
Published: 2025-04-23
Last modified: 2026-06-17

Description

TOTOLINK A800R V4.1.2cu.5137_B20200730 was found to contain a buffer overflow vulnerability in downloadFile.cgi through the v25 parameter.

Frequently asked questions

What is CVE-2025-28020?: TOTOLINK A800R V4.1.2cu.5137_B20200730 was found to contain a buffer overflow vulnerability in downloadFile.cgi through the v25 parameter.
How severe is CVE-2025-28020?: CVE-2025-28020 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2025-28020 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (25th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-28020?: CVE-2025-28020 affects Totolink A800r Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-28020?: 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-2025-28020 have an EU (EUVD) identifier?: Yes. CVE-2025-28020 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-12101.
When was CVE-2025-28020 published?: CVE-2025-28020 was published on 2025-04-23 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:totolink:a800r_firmware:4.1.2cu.5137_b20200730:*:*:*:*:*:*:*

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