How severe is CVE-2025-31363?

CVE-2025-31363 has a CVSS 3.x base score of 3.0, rated low severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2025-31363 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (16th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-31363?

CVE-2025-31363 primarily affects Mattermost Mattermost Server. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-31363?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2025-31363 have an EU (EUVD) identifier?

Yes. CVE-2025-31363 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-11357.

When was CVE-2025-31363 published?

CVE-2025-31363 was published on 2025-04-16 and last updated on 2026-06-17.

CVE-2025-31363

CVE-2025-31363 is a low-severity vulnerability in Mattermost Mattermost Server with a CVSS 3.x base score of 3.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Low (CVSS 3.x base score 3.0)
EPSS exploit prediction: 0% (16th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-11357
Affected product: Mattermost Mattermost Server
Published: 2025-04-16
Last modified: 2026-06-17

Description

Mattermost versions 10.4.x <= 10.4.2, 10.5.x <= 10.5.0, 9.11.x <= 9.11.9 fail to restrict domains the LLM can request to contact upstream which allows an authenticated user to exfiltrate data from an arbitrary server accessible to the victim via performing a prompt injection in the AI plugin's Jira tool.

Frequently asked questions

What is CVE-2025-31363?: Mattermost versions 10.4.x <= 10.4.2, 10.5.x <= 10.5.0, 9.11.x <= 9.11.9 fail to restrict domains the LLM can request to contact upstream which allows an authenticated user to exfiltrate data from an arbitrary server accessible to the victim via performing a prompt injection in the AI plugin's Jira tool.
How severe is CVE-2025-31363?: CVE-2025-31363 has a CVSS 3.x base score of 3.0, rated low severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2025-31363 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (16th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-31363?: CVE-2025-31363 primarily affects Mattermost Mattermost Server. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-31363?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-31363 have an EU (EUVD) identifier?: Yes. CVE-2025-31363 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-11357.
When was CVE-2025-31363 published?: CVE-2025-31363 was published on 2025-04-16 and last updated on 2026-06-17.

References

https://mattermost.com/security-updates

Affected products (2)

cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*
cpe:2.3:a:mattermost:mattermost_server:10.5.0:-:*:*:*:*:*:*

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