How severe is CVE-2025-28034?

CVE-2025-28034 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2025-28034 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-28034?

CVE-2025-28034 primarily affects Totolink A800r Firmware. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-28034?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2025-28034 have an EU (EUVD) identifier?

Yes. CVE-2025-28034 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-12218.

When was CVE-2025-28034 published?

CVE-2025-28034 was published on 2025-04-22 and last updated on 2026-06-17.

CVE-2025-28034

CVE-2025-28034 is a critical-severity vulnerability in Totolink A800r Firmware with a CVSS 3.x base score of 9.8. 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-78.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 1% (60th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-12218
Weakness: CWE-78
Affected product: Totolink A800r Firmware
Published: 2025-04-22
Last modified: 2026-06-17

Description

TOTOLINK A800R V4.1.2cu.5137_B20200730, A810R V4.1.2cu.5182_B20201026, A830R V4.1.2cu.5182_B20201102, A950RG V4.1.2cu.5161_B20200903, A3000RU V5.9c.5185_B20201128, and A3100R V4.1.2cu.5247_B20211129 were found to contain a pre-auth remote command execution vulnerability in the NTPSyncWithHost function through the hostTime parameter.

Frequently asked questions

What is CVE-2025-28034?: TOTOLINK A800R V4.1.2cu.5137_B20200730, A810R V4.1.2cu.5182_B20201026, A830R V4.1.2cu.5182_B20201102, A950RG V4.1.2cu.5161_B20200903, A3000RU V5.9c.5185_B20201128, and A3100R V4.1.2cu.5247_B20211129 were found to contain a pre-auth remote command execution vulnerability in the NTPSyncWithHost function through the hostTime parameter.
How severe is CVE-2025-28034?: CVE-2025-28034 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2025-28034 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-28034?: CVE-2025-28034 primarily affects Totolink A800r Firmware. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-28034?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2025-28034 have an EU (EUVD) identifier?: Yes. CVE-2025-28034 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-12218.
When was CVE-2025-28034 published?: CVE-2025-28034 was published on 2025-04-22 and last updated on 2026-06-17.

References

Affected products (6)

cpe:2.3:o:totolink:a800r_firmware:4.1.2cu.5137_b20200730:*:*:*:*:*:*:*
cpe:2.3:o:totolink:a810r_firmware:4.1.2cu.5182_b20201026:*:*:*:*:*:*:*
cpe:2.3:o:totolink:a830r_firmware:4.1.2cu.5182_b20201102:*:*:*:*:*:*:*
cpe:2.3:o:totolink:a950rg_firmware:4.1.2cu.5161_b20200903:*:*:*:*:*:*:*
cpe:2.3:o:totolink:a3000ru_firmware:5.9c.5185_b20201128:*:*:*:*:*:*:*
cpe:2.3:o:totolink:a3100r_firmware:4.1.2cu.5247_b20211129:*:*:*:*:*:*:*

More vulnerabilities in Totolink A800r 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-2025-28138 — Critical (CVSS 9.8): The TOTOLINK A800R V4.1.2cu.5137_B20200730 were found to contain a pre-auth remote command execution vulnerability in…
CVE-2022-26214 — Critical (CVSS 9.8): Totolink A830R V5.9c.4729_B20191112, A3100R V4.1.2cu.5050_B20200504, A950RG V4.1.2cu.5161_B20200903, A800R…
CVE-2022-26212 — Critical (CVSS 9.8): Totolink A830R V5.9c.4729_B20191112, A3100R V4.1.2cu.5050_B20200504, A950RG V4.1.2cu.5161_B20200903, A800R…
CVE-2022-26211 — Critical (CVSS 9.8): Totolink A830R V5.9c.4729_B20191112, A3100R V4.1.2cu.5050_B20200504, A950RG V4.1.2cu.5161_B20200903, A800R…

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