CVE-2026-5438

HIGH

Gzip Decompression Bomb via Content-Encoding Header

Title source: cna
STIX 2.1

Description

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.

Scores

CVSS v3 7.5
EPSS 0.0006
EPSS Percentile 17.0%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-770
Status published
Products (2)
Orthanc/DICOM Server < 1.12.10
orthanc-server/orthanc < 1.12.11
Published Apr 09, 2026
Tracked Since Apr 09, 2026