CVE-2026-58127

PACSgear MediaWriter 5.2.1 exposes a .NET Remoting TCP service on port 9000 via PacsgearMediaServerEngine.dll, registered with ObjectURIs RemoteObj and UIRemoteObj, without any authentication requirement. By exploiting the MarshalByRefObject object unmarshalling technique and implementing .NET WebClient class methods, an unauthenticated remote attacker can read and write arbitrary files on the host filesystem. The ObjectURIs are identical across all installations by default. Chaining the arbitrary file write primitive with DLL hijacking opportunities in the MediaWriter service (which runs as NT Authority\\SYSTEM and loads missing DLLs such as CRYPTBASE.DLL from the application directory) enables unauthenticated remote code execution as SYSTEM upon service restart.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://gist.github.com/VAMorales/dc679ecab30b7045fa07bf3249a034d8	Exploit Third Party Advisory
https://www.hyland.com/en/solutions/products/pacsgear	Product
https://www.vulncheck.com/advisories/pacsgear-mediawriter-unauthenticated-rce-via-net-remoting-tcp-service	Third Party Advisory VDB Entry

Configurations

Configuration 1 (hide)

cpe:2.3:a:hyland:pacsgear:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-07-01 16:16

Updated : 2026-07-09 02:37

NVD link : CVE-2026-58127

Mitre link : CVE-2026-58127

CVE.ORG link : CVE-2026-58127

JSON object : View

Products Affected

hyland

pacsgear

CWE

CWE-306

Missing Authentication for Critical Function

CWE-502

Deserialization of Untrusted Data

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