CVE-2026-126421

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

Published Nov 13, 2026 CVSS 4.0 · 5.3 Medium EPSS < 1% KEV · Not listed

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.

Analysis

No analysis available yet

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

openemr

unaffected

Version	Status	Constraints
`0`	affected	< 8.5.0
`8.5.0`	unaffected	—

No data.

No data available yet.

Remediation

No remediation available yet

Tracking

Advisories

No advisories available

Metrics

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact None

Vulnerable System Integrity Impact None

Vulnerable System Availability Impact Low

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

Attack Vector Network

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact Low

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploit prediction score: < 1% (0.373% probability within 30 days)

Key SSVC decision points have not yet been added.

References

Link	Providers
https://github.com/openemr/openemr/security/advisories/GHSA-3j3r-w7q7-h9fj
https://www.vulncheck.com/advisories/openemr-before-8.5.0-denial-of-service-via-labs-ajax-php-label-count

History

Nov 13, 2026 9:45 AM Description updated. Title updated. First appearance in the feed. Weaknesses updated. Affected versions updated. Affected vendors updated. Added references. Scoring metrics updated View changes

Type	Values Removed	Values Added
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.
Title		OpenEMR before 8.5.0 Denial of Service via labs_ajax.php Label Count
First Time appeared		Open-emr Open-emr openemr
Weaknesses		CWE-770
CPEs		cpe:2.3:a:open-emr:openemr::::::::
Vendors & Products		Open-emr Open-emr openemr
References		https://github.com/openemr/openemr/security/advisories/GHSA-3j3r-w7q7-h9fj https://www.vulncheck.com/advisories/openemr-before-8.5.0-denial-of-service-via-labs-ajax-php-label-count
Metrics		cvssV3_1 `{'score': 4.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L'}` cvssV4_0 `{'score': 5.3, 'vector': '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'}`