How severe is CVE-2025-13523?

CVE-2025-13523 has a CVSS 3.x base score of 7.7, rated high severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2025-13523 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (9th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-13523?

CVE-2025-13523 affects Mattermost Confluence. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-13523?

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-2025-13523 have an EU (EUVD) identifier?

Yes. CVE-2025-13523 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-206888.

When was CVE-2025-13523 published?

CVE-2025-13523 was published on 2026-02-06 and last updated on 2026-06-17.

CVE-2025-13523

CVE-2025-13523 is a high-severity vulnerability in Mattermost Confluence with a CVSS 3.x base score of 7.7. 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: High (CVSS 3.x base score 7.7)
EPSS exploit prediction: 0% (9th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-206888
Weakness: CWE-79
Affected product: Mattermost Confluence
Published: 2026-02-06
Last modified: 2026-06-17

Description

Mattermost Confluence plugin version <1.7.0 fails to properly escape user-controlled display names in HTML template rendering which allows authenticated Confluence users with malicious display names to execute arbitrary JavaScript in victim browsers via sending a specially crafted OAuth2 connection link that, when visited, renders the attacker's display name without proper sanitization. Mattermost Advisory ID: MMSA-2025-00557

Frequently asked questions

What is CVE-2025-13523?: Mattermost Confluence plugin version <1.7.0 fails to properly escape user-controlled display names in HTML template rendering which allows authenticated Confluence users with malicious display names to execute arbitrary JavaScript in victim browsers via sending a specially crafted OAuth2 connection link that, when visited, renders the attacker's display name without proper sanitization. Mattermost Advisory ID: MMSA-2025-00557
How severe is CVE-2025-13523?: CVE-2025-13523 has a CVSS 3.x base score of 7.7, rated high severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2025-13523 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (9th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-13523?: CVE-2025-13523 affects Mattermost Confluence. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-13523?: 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-2025-13523 have an EU (EUVD) identifier?: Yes. CVE-2025-13523 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-206888.
When was CVE-2025-13523 published?: CVE-2025-13523 was published on 2026-02-06 and last updated on 2026-06-17.

References

https://mattermost.com/security-updates

Affected products (1)

cpe:2.3:a:mattermost:confluence:*:*:*:*:*:mattermost:*:*

More vulnerabilities in Mattermost Confluence

CVE-2025-54525 — High (CVSS 7.5): Mattermost Confluence Plugin version <1.5.0 fails to handle unexpected request body which allows attackers to crash the…
CVE-2025-52931 — High (CVSS 7.5): Mattermost Confluence Plugin version <1.5.0 fails to handle unexpected request body which allows attackers to crash the…
CVE-2025-54478 — High (CVSS 7.2): Mattermost Confluence Plugin version <1.5.0 fails to enforce authentication of the user to the Mattermost instance…
CVE-2025-44004 — High (CVSS 7.2): Mattermost Confluence Plugin version <1.5.0 fails to check the authorization of the user to the Mattermost instance…
CVE-2025-48731 — Medium (CVSS 6.4): Mattermost Confluence Plugin version <1.5.0 fails to check the access of the user to the Confluence space which allows…
CVE-2025-54463 — Medium (CVSS 5.9): Mattermost Confluence Plugin version <1.5.0 fails to handle unexpected request body which allows attackers to crash the…

All CVEs affecting Mattermost Confluence →

Other CWE-79 (Cross-site Scripting (XSS)) vulnerabilities

CVE-2025-49410 — Critical (CVSS 10.0): Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Imran Emu TC…
CVE-2024-47875 — Critical (CVSS 10.0): DOMPurify is a DOM-only, super-fast, uber-tolerant XSS sanitizer for HTML, MathML and SVG. DOMpurify was vulnerable to…
CVE-2024-6886 — Critical (CVSS 10.0): Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in Gitea…
CVE-2023-45144 — Critical (CVSS 10.0): com.xwiki.identity-oauth:identity-oauth-ui is a package to aid in building identity and service providers based on…
CVE-2023-45138 — Critical (CVSS 10.0): Change Request is an pplication allowing users to request changes on a wiki without publishing the changes directly.…
CVE-2022-4361 — Critical (CVSS 10.0): Keycloak, an open-source identity and access management solution, has a cross-site scripting (XSS) vulnerability in the…

Browse all CWE-79 (Cross-site Scripting (XSS)) vulnerabilities →