How severe is CVE-2025-51691?

CVE-2025-51691 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2025-51691 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2025-51691?

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

Does CVE-2025-51691 have an EU (EUVD) identifier?

Yes. CVE-2025-51691 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-24568.

When was CVE-2025-51691 published?

CVE-2025-51691 was published on 2025-08-13 and last updated on 2026-06-17.

CVE-2025-51691

CVE-2025-51691 is a medium-severity vulnerability with a CVSS 3.x base score of 6.1. 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
EPSS exploit prediction: 0% (29th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-24568
Weakness: CWE-79
Published: 2025-08-13
Last modified: 2026-06-17

Description

Cross-Site Scripting (XSS) vulnerability found in MarkTwo commit e3a1d3f90cce4ea9c26efcbbf3a1cbfb9dcdb298 (May 2025) allows a remote attacker to execute arbitrary code via a crafted script input to the editor interface. The application does not properly sanitize user-supplied Markdown before rendering it. Successful exploitation could lead to session hijacking, credential theft, or arbitrary client-side code execution in the context of the victim's browser.

Frequently asked questions

What is CVE-2025-51691?: Cross-Site Scripting (XSS) vulnerability found in MarkTwo commit e3a1d3f90cce4ea9c26efcbbf3a1cbfb9dcdb298 (May 2025) allows a remote attacker to execute arbitrary code via a crafted script input to the editor interface. The application does not properly sanitize user-supplied Markdown before rendering it. Successful exploitation could lead to session hijacking, credential theft, or arbitrary client-side code execution in the context of the victim's browser.
How severe is CVE-2025-51691?: CVE-2025-51691 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2025-51691 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2025-51691?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-51691 have an EU (EUVD) identifier?: Yes. CVE-2025-51691 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-24568.
When was CVE-2025-51691 published?: CVE-2025-51691 was published on 2025-08-13 and last updated on 2026-06-17.

References

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 →