How severe is CVE-2026-31027?

CVE-2026-31027 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-2026-31027 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-31027?

CVE-2026-31027 affects Totolink A3600r Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-31027?

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-2026-31027 have an EU (EUVD) identifier?

Yes. CVE-2026-31027 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17913.

When was CVE-2026-31027 published?

CVE-2026-31027 was published on 2026-04-01 and last updated on 2026-06-17.

CVE-2026-31027

CVE-2026-31027 is a critical-severity vulnerability in Totolink A3600r 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-120.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 1% (44th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-17913
Weakness: CWE-120
Affected product: Totolink A3600r Firmware
Published: 2026-04-01
Last modified: 2026-06-17

Description

TOTOlink A3600R v5.9c.4959 contains a buffer overflow vulnerability in the setAppEasyWizardConfig interface of /lib/cste_modules/app.so. The vulnerability occurs because the rootSsid parameter is not properly validated for length, allowing remote attackers to trigger a buffer overflow, potentially leading to arbitrary code execution or denial of service.

Frequently asked questions

What is CVE-2026-31027?: TOTOlink A3600R v5.9c.4959 contains a buffer overflow vulnerability in the setAppEasyWizardConfig interface of /lib/cste_modules/app.so. The vulnerability occurs because the rootSsid parameter is not properly validated for length, allowing remote attackers to trigger a buffer overflow, potentially leading to arbitrary code execution or denial of service.
How severe is CVE-2026-31027?: CVE-2026-31027 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-2026-31027 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-31027?: CVE-2026-31027 affects Totolink A3600r Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-31027?: 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-2026-31027 have an EU (EUVD) identifier?: Yes. CVE-2026-31027 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17913.
When was CVE-2026-31027 published?: CVE-2026-31027 was published on 2026-04-01 and last updated on 2026-06-17.

References

https://github.com/SunnyYANGyaya/cuicuishark-sheep-fishIOT/blob/main/ToTolink/A3600R/rootSsid-setAppEasyWizardConfig.md

Affected products (1)

cpe:2.3:o:totolink:a3600r_firmware:5.9c.4959:*:*:*:*:*:*:*

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