How severe is CVE-2026-5566?

CVE-2026-5566 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-2026-5566 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-5566?

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-2026-5566 have an EU (EUVD) identifier?

Yes. CVE-2026-5566 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-19079.

When was CVE-2026-5566 published?

CVE-2026-5566 was published on 2026-04-05 and last updated on 2026-06-17.

CVE-2026-5566

CVE-2026-5566 is a high-severity vulnerability 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-119.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 9.0
CVSS v4: 7.4
EPSS exploit prediction: 0% (38th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-19079
Weakness: CWE-119
Published: 2026-04-05
Last modified: 2026-06-17

Description

A vulnerability was detected in UTT HiPER 1250GW up to 3.2.7-210907-180535. This affects the function strcpy of the file /goform/formNatStaticMap. Performing a manipulation of the argument NatBind results in buffer overflow. Remote exploitation of the attack is possible. The exploit is now public and may be used.

Frequently asked questions

What is CVE-2026-5566?: A vulnerability was detected in UTT HiPER 1250GW up to 3.2.7-210907-180535. This affects the function strcpy of the file /goform/formNatStaticMap. Performing a manipulation of the argument NatBind results in buffer overflow. Remote exploitation of the attack is possible. The exploit is now public and may be used.
How severe is CVE-2026-5566?: CVE-2026-5566 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-2026-5566 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-5566?: 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-2026-5566 have an EU (EUVD) identifier?: Yes. CVE-2026-5566 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-19079.
When was CVE-2026-5566 published?: CVE-2026-5566 was published on 2026-04-05 and last updated on 2026-06-17.

References

Other CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer) vulnerabilities

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