How severe is CVE-2026-24399?

CVE-2026-24399 has a CVSS 3.x base score of 9.3, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2026-24399 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (22nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-24399?

CVE-2026-24399 affects Chattermate. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-24399?

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-2026-24399 have an EU (EUVD) identifier?

Yes. CVE-2026-24399 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-4613.

When was CVE-2026-24399 published?

CVE-2026-24399 was published on 2026-01-24 and last updated on 2026-06-17.

CVE-2026-24399

CVE-2026-24399 is a critical-severity vulnerability in Chattermate with a CVSS 3.x base score of 9.3. 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-79.

Key facts

Severity: Critical (CVSS 3.x base score 9.3)
EPSS exploit prediction: 0% (22nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-4613
Weakness: CWE-79
Affected product: Chattermate
Published: 2026-01-24
Last modified: 2026-06-17

Description

ChatterMate is a no-code AI chatbot agent framework. In versions 1.0.8 and below, the chatbot accepts and executes malicious HTML/JavaScript payloads when supplied as chat input. Specifically, an <iframe> payload containing a javascript: URI can be processed and executed in the browser context. This allows access to sensitive client-side data such as localStorage tokens and cookies, resulting in client-side injection. This issue has been fixed in version 1.0.9.

Frequently asked questions

What is CVE-2026-24399?: ChatterMate is a no-code AI chatbot agent framework. In versions 1.0.8 and below, the chatbot accepts and executes malicious HTML/JavaScript payloads when supplied as chat input. Specifically, an <iframe> payload containing a javascript: URI can be processed and executed in the browser context. This allows access to sensitive client-side data such as localStorage tokens and cookies, resulting in client-side injection. This issue has been fixed in version 1.0.9.
How severe is CVE-2026-24399?: CVE-2026-24399 has a CVSS 3.x base score of 9.3, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2026-24399 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (22nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-24399?: CVE-2026-24399 affects Chattermate. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-24399?: 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-2026-24399 have an EU (EUVD) identifier?: Yes. CVE-2026-24399 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-4613.
When was CVE-2026-24399 published?: CVE-2026-24399 was published on 2026-01-24 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:chattermate:chattermate:*:*:*:*:*:*:*:*

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