How severe is CVE-2026-15688?

CVE-2026-15688 has a CVSS 4.0 base score of 9.2, rated critical severity.

Is CVE-2026-15688 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (2nd percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-15688?

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.

When was CVE-2026-15688 published?

CVE-2026-15688 was published on 2026-09-17 and last updated on 2026-09-18.

CVE-2026-15688

CVE-2026-15688 is a critical-severity vulnerability with a CVSS 4.0 base score of 9.2. 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-303.

Key facts

Severity: Critical (CVSS 4.0 base score 9.2)
EPSS exploit prediction: 0% (2nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-303
Published: 2026-09-17
Last modified: 2026-09-18

Description

Incorrect Implementation of Authentication Algorithm Vulnerability in Mitsubishi Electric GX Works3 and Motion Control Setting allows a local attacker to successfully authenticate even with an invalid block password by executing the affected product and modifying part of the executable module in memory, and thereby may be able to view, tamper with, destroy, or delete control programs.

Frequently asked questions

What is CVE-2026-15688?: Incorrect Implementation of Authentication Algorithm Vulnerability in Mitsubishi Electric GX Works3 and Motion Control Setting allows a local attacker to successfully authenticate even with an invalid block password by executing the affected product and modifying part of the executable module in memory, and thereby may be able to view, tamper with, destroy, or delete control programs.
How severe is CVE-2026-15688?: CVE-2026-15688 has a CVSS 4.0 base score of 9.2, rated critical severity.
Is CVE-2026-15688 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (2nd percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-15688?: 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.
When was CVE-2026-15688 published?: CVE-2026-15688 was published on 2026-09-17 and last updated on 2026-09-18.

References

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