Exploited Ransomware

CVE-2023-43208

NextGen Healthcare Mirth Connect · ERP, business applications and databases

NextGen Healthcare Mirth Connect Deserialization of Untrusted Data Vulnerability

At a glance

Exploited. Added to CISA’s catalog of exploited vulnerabilities on May 20, 2024.

Used in ransomware attacks, according to CISA.

Affected product: NextGen Healthcare Mirth Connect (category ERP, business applications and databases, indicative classification). Name in CISA’s catalog: NextGen Healthcare Mirth Connect.

What should I do?

Apply the patches or mitigations from NextGen Healthcare; if none are available, stop using the product.

Deadline set by CISA for US federal agencies: 21 days (due June 10, 2024). It only binds those agencies, but it is a useful measure of urgency.

The vendor’s specific advisory is listed in the NVD references: CVE-2023-43208 on the NVD website.

Original text of the required action (CISA)

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

Timeline

October 26, 2023 Vulnerability published Publication date (NVD)
May 20, 2024 Exploitation confirmed Added to CISA’s KEV catalog
June 10, 2024 CISA deadline Remediation deadline set for US federal agencies

The facts, with their sources

Exploitation confirmed: Yes, on May 20, 2024 Date added to the catalog of exploited vulnerabilities. Exploitation itself may have started earlier. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
Ransomware: Known use Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
Hunt for compromise: Not requested by CISA Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
CISA required action: Apply the patches or mitigations from NextGen Healthcare; if none are available, stop using the product. Rewritten by this site from CISA’s original text. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
CISA deadline: June 10, 2024, 21 days Set for US federal agencies: a measure of urgency, not an obligation elsewhere. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
Vulnerability published: October 26, 2023 Source: National Vulnerability Database (NVD), collected September 29, 2026 at 15:00 UTC
Product according to CISA: NextGen Healthcare Mirth Connect Filed by this site under “ERP, business applications and databases” (indicative classification). Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Technical detail of the score: attack vector, complexity, impact. Source: National Vulnerability Database (NVD), collected September 29, 2026 at 15:00 UTC

Severity and activity

9.8 / 10 CVSS severity: critical

Score from the NVD. Collected Sep 29, 2026.

— Probability of exploitation in the next 30 days (EPSS)

FIRST’s EPSS model. Since exploitation is already confirmed, this figure is mostly useful to compare activity. Collected Sep 29, 2026.

Description

NextGen Healthcare Mirth Connect before version 4.4.1 is vulnerable to unauthenticated remote code execution. Note that this vulnerability is caused by the incomplete patch of CVE-2023-37679.

NextGen Healthcare Mirth Connect contains a deserialization of untrusted data vulnerability that allows for unauthenticated remote code execution via a specially crafted request.

Summary from CISA (KEV catalog).

CERT-FR advisories

No advisory among the latest CERT-FR publications this site follows. That does not mean there are none.

Information reused under the Open Licence 2.0 (Etalab); the date of last update is shown for each advisory. This site is neither affiliated with nor endorsed by ANSSI.

Sources for this page

CISA KEV catalog: exploitation, date added, required action, deadline, ransomware.
NVD (NIST): CVSS severity, publication date, description, vendor references.
EPSS (FIRST): probability of exploitation.
CERT-FR: advisories and alerts (in French).
Brand and category: indicative classification by this site (method).