CVE-2026-35403

CVE-2026-35403 is a medium-severity vulnerability in Mcgill Loris with a CVSS 3.x base score of 6.5. 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-79.

Key facts

Description

LORIS (Longitudinal Online Research and Imaging System) is a self-hosted web application that provides data- and project-management for neuroimaging research. From 15.10 to before 27.0.3 and 28.0.1, there is a potential for a cross-site scripting attack in the survey_accounts module if a user provides an invalid visit label. While the data is properly JSON encoded, the Content-Type header is not set causing the web browser to interpret the payload as HTML, opening the possibility of a cross-site scripting if a user is tricked into following an invalid link. This vulnerability is fixed in 27.0.3 and 28.0.1.

Frequently asked questions

What is CVE-2026-35403?
LORIS (Longitudinal Online Research and Imaging System) is a self-hosted web application that provides data- and project-management for neuroimaging research. From 15.10 to before 27.0.3 and 28.0.1, there is a potential for a cross-site scripting attack in the survey_accounts module if a user provides an invalid visit label. While the data is properly JSON encoded, the Content-Type header is not set causing the web browser to interpret the payload as HTML, opening the possibility of a cross-site scripting if a user is tricked into following an invalid link. This vulnerability is fixed in 27.0.3 and 28.0.1.
How severe is CVE-2026-35403?
CVE-2026-35403 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity low, and availability none.
Is CVE-2026-35403 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-35403?
CVE-2026-35403 primarily affects Mcgill Loris. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-35403?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-35403 have an EU (EUVD) identifier?
Yes. CVE-2026-35403 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-20578.
When was CVE-2026-35403 published?
CVE-2026-35403 was published on 2026-04-08 and last updated on 2026-06-17.

References

Affected products (2)

More vulnerabilities in Mcgill Loris

All CVEs affecting Mcgill Loris →

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

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