CVE-2026-5438 json
Gzip Decompression Bomb via Content-Encoding Header
published 2026-04-09 7 mo ago modified 2026-10-26 14 d ago also EUVD-2026-20914
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 42%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- orthanc-server orthanc 1.12.11
- orthanc Debian 14 1.12.10+dfsg-4
debian advisories DEBIAN-CVE-2026-5438
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 6 mo ago
Exploit prediction
0.49% chance of exploitation in the next 30 days, higher than 42% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CISA ADP | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Affected products
- Orthanc DICOM Server
Classification
- Weakness
-
- CWE-770 Allocation of Resources Without Limits or Throttling
References
-
orthanc-server.com
/
product
-
machinespirits.de
/
not-applicable
-
kb.cert.org
/vuls/id/536588
third-party-advisory, vdb-entry
Sources
- CVE List CVE-2026-5438
- NVD CVE-2026-5438
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.