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CVE-2026-126423 OpenEMR before 8.5.0 Denial of Service via ZIP Upload Decompression

5.3 mediumEPSS 0.4%

Medium (5.3) in openemr openemr. EPSS 0.4% estimated probability of exploitation activity in the next 30 days.

On this page
OpenEMR before 8.5.0 contains a denial of service vulnerability in four ZIP upload paths that read uncompressed entries into memory without size or ratio checks. Authenticated billing or Carecoordination users can upload highly compressed ZIP archives to exhaust PHP memory and worker pools, making OpenEMR unavailable.

Severity

CVSS 4.0

5.3 medium
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

CVSS 3.1

4.3 medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
EPSS
0.4% estimated probability of exploitation activity in the next 30 days; 32nd percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
CISA's assessment (SSVC)
Exploitation: none · 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-409 Improper Handling of Highly Compressed Data (Data Amplification)
Published
Modified
Assigned by
VulnCheck (CNA)
NVD analysis
Awaiting analysis
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

References

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