How severe is CVE-2025-71021?

CVE-2025-71021 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2025-71021 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-71021?

CVE-2025-71021 affects Tenda Ax1806 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-71021?

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-2025-71021 have an EU (EUVD) identifier?

Yes. CVE-2025-71021 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-2444.

When was CVE-2025-71021 published?

CVE-2025-71021 was published on 2026-01-14 and last updated on 2026-06-17.

CVE-2025-71021

CVE-2025-71021 is a high-severity vulnerability in Tenda Ax1806 Firmware with a CVSS 3.x base score of 7.5. 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-121.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 0% (31st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-2444
Weakness: CWE-121
Affected product: Tenda Ax1806 Firmware
Published: 2026-01-14
Last modified: 2026-06-17

Description

Tenda AX-1806 v1.0.0.1 was discovered to contain a stack overflow in the serverName parameter of the sub_65A28 function. This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted request.

Frequently asked questions

What is CVE-2025-71021?: Tenda AX-1806 v1.0.0.1 was discovered to contain a stack overflow in the serverName parameter of the sub_65A28 function. This vulnerability allows attackers to cause a Denial of Service (DoS) via a crafted request.
How severe is CVE-2025-71021?: CVE-2025-71021 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2025-71021 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-71021?: CVE-2025-71021 affects Tenda Ax1806 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-71021?: 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-2025-71021 have an EU (EUVD) identifier?: Yes. CVE-2025-71021 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-2444.
When was CVE-2025-71021 published?: CVE-2025-71021 was published on 2026-01-14 and last updated on 2026-06-17.

References

https://github.com/0-fool/VulnbyCola/blob/main/Tenda/AX-1806/7/1.md

Affected products (1)

cpe:2.3:o:tenda:ax1806_firmware:1.0.0.1:*:*:*:*:*:*:*

More vulnerabilities in Tenda Ax1806 Firmware

CVE-2024-44557 — Critical (CVSS 9.8): Tenda AX1806 v1.0.0.1 contains a stack overflow via the iptv.stb.mode parameter in the function setIptvInfo.
CVE-2024-44555 — Critical (CVSS 9.8): Tenda AX1806 v1.0.0.1 contains a stack overflow via the iptv.city.vlan parameter in the function setIptvInfo.
CVE-2024-44553 — Critical (CVSS 9.8): Tenda AX1806 v1.0.0.1 contains a stack overflow via the iptv.stb.mode parameter in the function formGetIptv.
CVE-2024-44552 — Critical (CVSS 9.8): Tenda AX1806 v1.0.0.1 contains a stack overflow via the adv.iptv.stballvlans parameter in the function formGetIptv.
CVE-2024-44551 — Critical (CVSS 9.8): Tenda AX1806 v1.0.0.1 contains a stack overflow via the iptv.city.vlan parameter in the function formGetIptv.
CVE-2024-44550 — Critical (CVSS 9.8): Tenda AX1806 v1.0.0.1 contains a stack overflow via the adv.iptv.stbpvid parameter in the function formGetIptv.

All CVEs affecting Tenda Ax1806 Firmware →

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