CVE-2026-40508
OpenEMR < 8.3.0 Stored XSS via Patient Portal Template Import Handler
No known exploitation. EPSS puts it in the 20th percentile. No fix published yet.
What to do
No fixed build or workaround is published yet. Limit exposure and watch for a patch.
Steps
Written by AI from the record- Check whether your OpenEMR installation is older than 8.3.0 and whether staff use Forms Administration or patient portal template imports.
- Upgrade OpenEMR to 8.3.0.
- Until upgraded, restrict Forms Administration permissions and pause template imports from untrusted sources.
- Review recently imported portal templates for unexpected embedded web code.
What it is
From the CVE record
OpenEMR before 8.3.0 contains a stored cross-site scripting vulnerability in the patient portal template import handler that allows authenticated attackers with Forms Administration permissions to upload template files containing arbitrary HTML or JavaScript. Attackers can inject malicious scripts through the template upload functionality, which are stored without sanitization and execute in the browser of any other Forms Administration user who views the template in the HTML editor.
In plain language
Written by AI from the recordOpenEMR before 8.3.0 lets a permitted administrator hide harmful web code in a patient-portal template, so affected businesses should schedule an upgrade soon.
Stored XSS in the OpenEMR patient portal template import handler allows authenticated users with Forms Administration permissions to upload unsanitized HTML or JavaScript that executes when another Forms Administration user opens the template editor.
If you're affected
- Administrator session misuse
- Patient portal changes
- Potential patient-data exposure
- Workflow disruption
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
0.3% chance of exploitation activity in the next 30 days, which ranks it in the 20th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
7 events over 29 days, from the signal feeds we watch.
- OpenVAS check added
- Record updated
- Publishedweakness classified, att&ck mapped, record updated, record updated
Affected products
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
Scored 5.4 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required LowRequires basic user-level privileges
- User Interaction RequiredA user must click a link, open a file, or perform some action
Scope
- Scope ChangedThe exploit can affect other components (e.g. sandbox escape, host compromise from VM)
Impact if exploited
- Confidentiality LowSome restricted information is disclosed, but limited in scope
- Integrity LowData modification is possible but limited in scope or consequence
- Availability NoneNo availability impact
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
Sources
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