CVE-2026-5438

A gzip decompression bomb vulnerability exists when Orthanc processes HTTP request with `Content-Encoding: gzip`. The server does not enforce limits on decompressed size and allocates memory based on attacker-controlled compression metadata. A specially crafted gzip payload can trigger excessive memory allocation and exhaust system memory.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://kb.cert.org/vuls/id/536588	Third Party Advisory VDB Entry
https://www.machinespirits.de/	Not Applicable
https://www.orthanc-server.com/	Product

Configurations

Configuration 1 (hide)

cpe:2.3:a:orthanc-server:orthanc:*:*:*:*:*:*:*:*

History

26 Oct 2026, 00:10

Type	Values Removed	Values Added
Summary		(es) Una vulnerabilidad de bomba de descompresión gzip existe cuando Orthanc procesa solicitudes HTTP con ’Content-Encoding: gzip’. El servidor no impone límites en el tamaño descomprimido y asigna memoria basándose en metadatos de compresión controlados por el atacante. Una carga útil gzip especialmente diseñada puede desencadenar una asignación excesiva de memoria y agotar la memoria del sistema.

Information

Published : 2026-04-09 15:16

Updated : 2026-10-26 00:10

NVD link : CVE-2026-5438

Mitre link : CVE-2026-5438

CVE.ORG link : CVE-2026-5438

JSON object : View

Products Affected

orthanc-server

orthanc

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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