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TI-2026-04762 Aliases CVE-2026-5439GHSA-6cmv-pvcc-pf5h

Memory Exhaustion via Forged ZIP Metadata

Priority LOW 39CWE-770Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-770.

Summary

A memory exhaustion vulnerability exists in ZIP archive processing. Orthanc automatically extracts ZIP archives uploaded to certain endpoints and trusts metadata fields describing the uncompressed size of archived files. An attacker can craft a small ZIP archive containing a forged size value, causing the server to allocate extremely large buffers during extraction.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00433 37th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
OrthancDICOM Serverup to 1.12.10—No fix listedCNA
  • DICOM Server VendorOrthanc Affected up to 1.12.10 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:orthanc-server:orthanc:*:*:*:*:*:*:*:*before 1.12.11VulnerableOrthanc
  • cpe:2.3:a:orthanc-server:orthanc:*:*:*:*:*:*:*:* Versions before 1.12.11 Vulnerable ·Orthanc

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-5439
  2. 2026-10-03 Alias added: GHSA-6cmv-pvcc-pf5h
  3. 2026-10-25 EPSS moved to the below the 50th percentile
  4. 2026-10-25 Priority changed: MEDIUM → LOW

References

  • TI-2025-00759 Orthanc Server Missing Authentication for Critical Function CVSS 4.0CRITICAL 9.2
  • TI-2026-04766 Heap Buffer Overflow in DICOM Image Decoder (Palette Color Decode) CVSS 3.1CRITICAL 9.8
  • TI-2026-04765 Heap Buffer Overflow in DICOM Image Decoder via VR UL Dimensions CVSS 3.1CRITICAL 9.8
  • TI-2023-16538 Orthanc before 1.12.0 allows authenticated users with access to the Orthanc API to… CVSS 3.1HIGH 8.8
  • TI-2026-04768 Out-of-Bounds Read in DicomImageDecoder (DecodeLookupTable) CVSS 3.1CRITICAL 9.1
  • TI-2026-04763 Memory Exhaustion via Unbounded Content-Length CVSS 3.1HIGH 7.5
See all 11 →

Sources