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.
CVE-2026-40508
MEDIUMPre-NVD 5.45.4—Trending — 4 sources updated this weekElevated
EchelonGraph scoreHIGH confidence
Score 5.4 from GitHub Security Advisory published 2026-08-19. a secondary CVSS source baseline 5.4; sources differ by 0.0.
Triggered by: GitHub Security Advisory CVSS
Sources: ghsa, secondary
5.4EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
- Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.4Exploit: Elevated riskExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 5.4
- EG Score
- 5.4(high)
- EG Risk
- 40(Track)EG Risk 40/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity54% × 45%Exploitation40% × 40%Automatability0% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 0%
- EPSS %ILE
- 7%
- KEV
- Not listed
Published
August 19, 2026
Last Modified
August 19, 2026
Advisory Details (4)
Auto-updated Aug 19, 2026🔬 Proof of concept available. Patch available. Sources: github, github_release, github_commit.
generic
OpenEMR < 8.3.0 Stored XSS via Patient Portal Template Import Handler | Advisories | VulnCheck
https://www.vulncheck.com/advisories/openemr-stored-xss-via-patient-portal-template-import-handlergithub_commit
commit ba316dd1d8de (openemr/openemr)
Fix landed in openemr/openemr commit ba316dd1d8de — awaiting tagged release
https://github.com/openemr/openemr/commit/ba316dd1d8de1291102da3f20f64240729ff899egithub_release Patch Available
OpenEMR 8.3.0
Patch available: openemr/openemr v8_3_0
https://github.com/openemr/openemr/releases/tag/v8_3_0github Patch Available🟡 PoC Available
/portal/import_template.php template_files[] Stored Cross-Site Scripting · Advisory · openemr/openemr · GitHub
https://github.com/openemr/openemr/security/advisories/GHSA-5293-8q47-cf44Vendor Advisories for CVE-2026-40508(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 7× in last 7d / 7× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-08-20 22:55 UTCEPSS rescore
- 2026-08-20 15:07 UTCGHSA enrichment
- 2026-08-19 16:24 UTCEG score recompute
- 2026-08-19 16:24 UTCGHSA enrichment
- 2026-08-19 15:24 UTCEG score recompute
- 2026-08-19 14:57 UTCEG score recompute
- 2026-08-19 14:57 UTCMITRE cvelistV5first tracked
Frequently asked(5)
What is CVE-2026-40508?
CVE-2026-40508 is a medium vulnerability published on August 19, 2026. 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…
When was CVE-2026-40508 disclosed?
CVE-2026-40508 was first published in the National Vulnerability Database on August 19, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-40508 actively exploited?
CVE-2026-40508 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 93.1% of all scored CVEs.
What is the CVSS score of CVE-2026-40508?
CVE-2026-40508 has a CVSS v3 base score of 5.4 (NVD).
How do I remediate CVE-2026-40508?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-40508, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-40508
Is Your Infrastructure Affected by CVE-2026-40508?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.