How severe is CVE-2026-3254?

CVE-2026-3254 has a CVSS 3.x base score of 3.5, rated low severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2026-3254 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (5th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-3254?

CVE-2026-3254 primarily affects Gitlab. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-3254?

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

Does CVE-2026-3254 have an EU (EUVD) identifier?

Yes. CVE-2026-3254 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-24961.

When was CVE-2026-3254 published?

CVE-2026-3254 was published on 2026-04-22 and last updated on 2026-06-17.

CVE-2026-3254

CVE-2026-3254 is a low-severity vulnerability in Gitlab with a CVSS 3.x base score of 3.5. 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-1021.

Key facts

Severity: Low (CVSS 3.x base score 3.5)
EPSS exploit prediction: 0% (5th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-24961
Weakness: CWE-1021
Affected product: Gitlab
Published: 2026-04-22
Last modified: 2026-06-17

Description

GitLab has remediated an issue in GitLab CE/EE affecting all versions from 18.11 before 18.11.1 that under certain conditions could have allowed an authenticated user to load unauthorized content into another user's browser due to improper input validation in the Mermaid sandbox.

Frequently asked questions

What is CVE-2026-3254?: GitLab has remediated an issue in GitLab CE/EE affecting all versions from 18.11 before 18.11.1 that under certain conditions could have allowed an authenticated user to load unauthorized content into another user's browser due to improper input validation in the Mermaid sandbox.
How severe is CVE-2026-3254?: CVE-2026-3254 has a CVSS 3.x base score of 3.5, rated low severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2026-3254 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (5th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-3254?: CVE-2026-3254 primarily affects Gitlab. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-3254?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-3254 have an EU (EUVD) identifier?: Yes. CVE-2026-3254 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-24961.
When was CVE-2026-3254 published?: CVE-2026-3254 was published on 2026-04-22 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:gitlab:gitlab:18.11.0:*:*:*:community:*:*:*
cpe:2.3:a:gitlab:gitlab:18.11.0:*:*:*:enterprise:*:*:*

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