How severe is CVE-2025-13352?

CVE-2025-13352 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 none, integrity low, and availability none.

Is CVE-2025-13352 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (4th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-13352?

CVE-2025-13352 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-13352?

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

Does CVE-2025-13352 have an EU (EUVD) identifier?

Yes. CVE-2025-13352 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-203891.

When was CVE-2025-13352 published?

CVE-2025-13352 was published on 2025-12-17 and last updated on 2026-06-17.

CVE-2025-13352

CVE-2025-13352 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. The underlying weakness is classified as CWE-1287.

Key facts

Severity: Low (CVSS 3.x base score 3.0)
EPSS exploit prediction: 0% (4th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-203891
Weakness: CWE-1287
Affected product: Mattermost Mattermost Server
Published: 2025-12-17
Last modified: 2026-06-17

Description

Mattermost versions 10.11.x <= 10.11.6 and Mattermost GitHub plugin versions <=2.4.0 fail to validate plugin bot identity in reaction forwarding which allows attackers to hijack the GitHub reaction feature to make users add reactions to arbitrary GitHub objects via crafted notification posts.

Frequently asked questions

What is CVE-2025-13352?: Mattermost versions 10.11.x <= 10.11.6 and Mattermost GitHub plugin versions <=2.4.0 fail to validate plugin bot identity in reaction forwarding which allows attackers to hijack the GitHub reaction feature to make users add reactions to arbitrary GitHub objects via crafted notification posts.
How severe is CVE-2025-13352?: CVE-2025-13352 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 none, integrity low, and availability none.
Is CVE-2025-13352 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (4th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-13352?: CVE-2025-13352 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-13352?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-13352 have an EU (EUVD) identifier?: Yes. CVE-2025-13352 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-203891.
When was CVE-2025-13352 published?: CVE-2025-13352 was published on 2025-12-17 and last updated on 2026-06-17.

References

https://mattermost.com/security-updates

Affected products (1)

cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*

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