How severe is CVE-2026-40589?

CVE-2026-40589 has a CVSS 3.x base score of 7.6, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity high, and availability low.

Is CVE-2026-40589 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (14th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-40589?

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-2026-40589 have an EU (EUVD) identifier?

Yes. CVE-2026-40589 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-24184.

When was CVE-2026-40589 published?

CVE-2026-40589 was published on 2026-04-21 and last updated on 2026-06-17.

CVE-2026-40589

CVE-2026-40589 is a high-severity vulnerability with a CVSS 3.x base score of 7.6. 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-639.

Key facts

Severity: High (CVSS 3.x base score 7.6)
EPSS exploit prediction: 0% (14th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-24184
Weakness: CWE-639
Published: 2026-04-21
Last modified: 2026-06-17

Description

FreeScout is a free self-hosted help desk and shared mailbox. Prior to version 1.8.214, a low-privileged agent can edit a visible customer and add an email address already owned by a hidden customer in another mailbox. The server discloses the hidden customer’s name and profile URL in the success flash, reassigns the hidden email to the visible customer, and rebinds hidden-mailbox conversations for that email to the visible customer. Version 1.8.214 fixes the issue.

Frequently asked questions

What is CVE-2026-40589?: FreeScout is a free self-hosted help desk and shared mailbox. Prior to version 1.8.214, a low-privileged agent can edit a visible customer and add an email address already owned by a hidden customer in another mailbox. The server discloses the hidden customer’s name and profile URL in the success flash, reassigns the hidden email to the visible customer, and rebinds hidden-mailbox conversations for that email to the visible customer. Version 1.8.214 fixes the issue.
How severe is CVE-2026-40589?: CVE-2026-40589 has a CVSS 3.x base score of 7.6, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity high, and availability low.
Is CVE-2026-40589 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (14th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-40589?: 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-2026-40589 have an EU (EUVD) identifier?: Yes. CVE-2026-40589 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-24184.
When was CVE-2026-40589 published?: CVE-2026-40589 was published on 2026-04-21 and last updated on 2026-06-17.

References

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