How severe is CVE-2025-28021?

CVE-2025-28021 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-2025-28021 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-2025-28021?

CVE-2025-28021 affects Totolink A810r Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-28021?

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-2025-28021 have an EU (EUVD) identifier?

Yes. CVE-2025-28021 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-12091.

When was CVE-2025-28021 published?

CVE-2025-28021 was published on 2025-04-23 and last updated on 2026-06-17.

CVE-2025-28021

CVE-2025-28021 is a high-severity vulnerability in Totolink A810r 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-2025-12091
Weakness: CWE-120
Affected product: Totolink A810r Firmware
Published: 2025-04-23
Last modified: 2026-06-17

Description

TOTOLINK A810R V4.1.2cu.5182_B20201026 was found to contain a buffer overflow vulnerability in the downloadFile.cgi through the v14 and v3 parameters

Frequently asked questions

What is CVE-2025-28021?: TOTOLINK A810R V4.1.2cu.5182_B20201026 was found to contain a buffer overflow vulnerability in the downloadFile.cgi through the v14 and v3 parameters
How severe is CVE-2025-28021?: CVE-2025-28021 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-2025-28021 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-2025-28021?: CVE-2025-28021 affects Totolink A810r Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-28021?: 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-2025-28021 have an EU (EUVD) identifier?: Yes. CVE-2025-28021 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-12091.
When was CVE-2025-28021 published?: CVE-2025-28021 was published on 2025-04-23 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:totolink:a810r_firmware:4.1.2cu.5182_b20201026:*:*:*:*:*:*:*

More vulnerabilities in Totolink A810r Firmware

CVE-2025-28036 — Critical (CVSS 9.8): TOTOLINK A950RG V4.1.2cu.5161_B20200903 was found to contain a pre-auth remote command execution vulnerability in the…
CVE-2025-28035 — Critical (CVSS 9.8): TOTOLINK A830R V4.1.2cu.5182_B20201102 was found to contain a pre-auth remote command execution vulnerability in the…
CVE-2025-28037 — Critical (CVSS 9.8): TOTOLINK A810R V4.1.2cu.5182_B20201026 and A950RG V4.1.2cu.5161_B20200903 were found to contain a pre-auth remote…
CVE-2025-28024 — Critical (CVSS 9.8): TOTOLINK A810R V4.1.2cu.5182_B20201026 was found to contain a buffer overflow vulnerability in the cstecgi.cgi
CVE-2025-28034 — Critical (CVSS 9.8): TOTOLINK A800R V4.1.2cu.5137_B20200730, A810R V4.1.2cu.5182_B20201026, A830R V4.1.2cu.5182_B20201102, A950RG…
CVE-2025-28137 — Critical (CVSS 9.8): The TOTOLINK A810R V4.1.2cu.5182_B20201026 were found to contain a pre-auth remote command execution vulnerability in…

All CVEs affecting Totolink A810r Firmware →

Other CWE-120 (Classic Buffer Overflow) vulnerabilities

CVE-2025-48611 — Critical (CVSS 10.0): In DeviceId of DeviceId.java, there is a possible desync in persistence due to a missing bounds check. This could lead…
CVE-2026-24823 — Critical (CVSS 10.0): Out-of-bounds Write, Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') vulnerability in FASTSHIFT…
CVE-2026-24810 — Critical (CVSS 10.0): Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') vulnerability in rethinkdb (src/cjson modules).…
CVE-2026-24800 — Critical (CVSS 10.0): Out-of-bounds Write, Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') vulnerability in tildearrow…
CVE-2025-9962 — Critical (CVSS 10.0): A buffer overflow vulnerability in Novakon P series allows attackers to gain root permission without prior…
CVE-2010-10016 — Critical (CVSS 10.0): BS.Player version 2.57 (build 1051) contains a vulnerability in its playlist import functionality. When processing .m3u…

Browse all CWE-120 (Classic Buffer Overflow) vulnerabilities →