CVE-2026-126421

OpenEMR before 8.5.0 Denial of Service via labs_ajax.php Label Count

  • Medium 5.3

Description

OpenEMR before 8.5.0 contains an uncontrolled resource consumption vulnerability that allows authenticated users with patients/med access to exhaust PHP workers via an unbounded count parameter. Attackers can send print_labels requests to labs_ajax.php with huge counts, forcing mPDF page and barcode generation that makes OpenEMR unavailable.

Key facts

Published
13 Nov 2026
Last changed
13 Nov 2026
Assigned by
VulnCheck
EPSS
0.284% likely to be exploited in the next 30 days, higher than 21.15% of CVEs (scores for 15 Nov 2026)

Severity scores

Each score is shown as its source gave it. They are not averaged or merged.

  • 5.3CVSS 4.0, Mediumfrom the CNA (VulnCheck)CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
  • 4.3CVSS 3.1, Mediumfrom the CNA (VulnCheck)CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

Historical context and remediation

This reference retains the original CVE publication date. A recent record update does not mean a new attack occurred.

No separately sourced impact summary is available on this page yet. Consult the description, version data and dated exploitation evidence.

No explicit remediation statement is available on this page yet. Consult the original record and vendor references before choosing a fix.

Version statuses below come from the CNA. An “unaffected” version is not necessarily a currently supported release or proof of a patch date. EPSS is a dated risk estimate, not a count of historical attacks.

Read the original CVE record.

Affected products

VendorProductVersions
openemropenemr
  • Default status: unaffected
  • 0 up to but excluding 8.5.0 (affected)
  • 8.5.0 (unaffected)

Timeline

  1. 13 Nov 2026 Published

Weakness

References