How severe is CVE-2025-12239?

CVE-2025-12239 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-2025-12239 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-2025-12239?

CVE-2025-12239 affects Totolink A3300r Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-12239?

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-2025-12239 have an EU (EUVD) identifier?

Yes. CVE-2025-12239 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-36098.

When was CVE-2025-12239 published?

CVE-2025-12239 was published on 2025-10-27 and last updated on 2026-06-17.

CVE-2025-12239

CVE-2025-12239 is a high-severity vulnerability in Totolink A3300r 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-120.

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-2025-36098
Weakness: CWE-120
Affected product: Totolink A3300r Firmware
Published: 2025-10-27
Last modified: 2026-06-17

Description

A weakness has been identified in TOTOLINK A3300R 17.0.0cu.557_B20221024. The impacted element is the function setDdnsCfg of the file /cgi-bin/cstecgi.cgi. Executing manipulation can lead to buffer overflow. The attack may be performed from remote. The exploit has been made available to the public and could be exploited.

Frequently asked questions

What is CVE-2025-12239?: A weakness has been identified in TOTOLINK A3300R 17.0.0cu.557_B20221024. The impacted element is the function setDdnsCfg of the file /cgi-bin/cstecgi.cgi. Executing manipulation can lead to buffer overflow. The attack may be performed from remote. The exploit has been made available to the public and could be exploited.
How severe is CVE-2025-12239?: CVE-2025-12239 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-2025-12239 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-2025-12239?: CVE-2025-12239 affects Totolink A3300r Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-12239?: 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-2025-12239 have an EU (EUVD) identifier?: Yes. CVE-2025-12239 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-36098.
When was CVE-2025-12239 published?: CVE-2025-12239 was published on 2025-10-27 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:totolink:a3300r_firmware:17.0.0cu.557_b20221024:*:*:*:*:*:*:*

More vulnerabilities in Totolink A3300r Firmware

CVE-2026-31181 — Critical (CVSS 9.8): An issue was discovered in ToToLink A3300R firmware v17.0.0cu.557_B20221024 allowing attackers to execute arbitrary…
CVE-2026-31178 — Critical (CVSS 9.8): An issue was discovered in ToToLink A3300R firmware v17.0.0cu.557_B20221024 allowing attackers to execute arbitrary…
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CVE-2026-31170 — Critical (CVSS 9.8): An issue was discovered in ToToLink A3300R firmware v17.0.0cu.557_B20221024 allowing attackers to execute arbitrary…
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