How severe is CVE-2026-40496?

CVE-2026-40496 has a CVSS 3.x base score of 9.1, 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 none.

Is CVE-2026-40496 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-40496?

CVE-2026-40496 affects Freescout. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-40496?

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-2026-40496 have an EU (EUVD) identifier?

Yes. CVE-2026-40496 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-24049.

When was CVE-2026-40496 published?

CVE-2026-40496 was published on 2026-04-21 and last updated on 2026-06-17.

CVE-2026-40496

CVE-2026-40496 is a critical-severity vulnerability in Freescout with a CVSS 3.x base score of 9.1. 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-330.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
CVSS v4: 8.8
EPSS exploit prediction: 0% (32nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-24049
Weakness: CWE-330
Affected product: Freescout
Published: 2026-04-21
Last modified: 2026-06-17

Description

FreeScout is a free self-hosted help desk and shared mailbox. Prior to version 1.8.213, attachment download tokens are generated using a weak and predictable formula: `md5(APP_KEY + attachment_id + size)`. Since attachment_id is sequential and size can be brute-forced in a small range, an unauthenticated attacker can forge valid tokens and download any private attachment without credentials. Version 1.8.213 fixes the issue.

Frequently asked questions

What is CVE-2026-40496?: FreeScout is a free self-hosted help desk and shared mailbox. Prior to version 1.8.213, attachment download tokens are generated using a weak and predictable formula: `md5(APP_KEY + attachment_id + size)`. Since attachment_id is sequential and size can be brute-forced in a small range, an unauthenticated attacker can forge valid tokens and download any private attachment without credentials. Version 1.8.213 fixes the issue.
How severe is CVE-2026-40496?: CVE-2026-40496 has a CVSS 3.x base score of 9.1, 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 none.
Is CVE-2026-40496 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-40496?: CVE-2026-40496 affects Freescout. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-40496?: 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-2026-40496 have an EU (EUVD) identifier?: Yes. CVE-2026-40496 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-24049.
When was CVE-2026-40496 published?: CVE-2026-40496 was published on 2026-04-21 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:freescout:freescout:*:*:*:*:*:*:*:*

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