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CVE-2026-126493 OpenEMR before 8.5.0 Stored XSS via OnsitePortalActivity tableArgs

4.8 mediumExploit referenceEPSS 0.2%

Medium (4.8) in open-emr openemr. EPSS 0.2% estimated probability of exploitation activity in the next 30 days.

On this page
OpenEMR before 8.5.0 contains a stored cross-site scripting vulnerability that allows low-privileged patient portal users to inject JavaScript via the tableArgs field of the onsiteportalactivity API. Attackers can store a payload with spaces that breaks out of an unquoted data-delete-id attribute, executing script when providers click the delete button on the audit review page.

Severity

CVSS 4.0

4.8 medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N

CVSS 3.1

5.4 medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
EPSS
0.2% estimated probability of exploitation activity in the next 30 days; 15th percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
CISA's assessment (SSVC)
Exploitation: PoC · Automatable: no · Technical impact: partial, assessed 2026-11-13. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
CWE
CWE-79 Improper Neutralization of Input During Web Page Generation (Cross-site Scripting)
OWASP Top 10
A05:2025 Injection
Published
Modified
Assigned by
VulnCheck (CNA)
NVD analysis
Analyzed, since modified
Record from
the NVD, synced

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Affected

Versions

From the CNA's record in the CVE List.

ProductAffected
openemrbefore 8.5.0

Fix and patched versions

Attack patterns (CAPEC)

  • CAPEC-63 Cross-Site Scripting (XSS) Likelihood: High · Severity: Very High
  • CAPEC-85 AJAX Footprinting Likelihood: High · Severity: Low
  • CAPEC-209 XSS Using MIME Type Mismatch Severity: Medium
  • CAPEC-588 DOM-Based XSS Likelihood: High · Severity: Very High
  • CAPEC-591 Reflected XSS Likelihood: High · Severity: Very High
  • CAPEC-592 Stored XSS Likelihood: High · Severity: Very High

The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.

History

  1. Analyzed by the NVD

Changes since this site first stored the record. The same for every record: /api/public/changes.

References

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