Which versions of Unblu Spark are affected by CVE-2025-3519?

Organizations using An authorization bypass in Unblu Spark face moderate risk from CVE-2025-3519, a IDOR vulnerability rated CVSS 7.0.

How to fix or mitigate CVE-2025-3519?

Within 7 days: Identify all affected systems and apply vendor patches promptly. Monitor vendor channels for patch availability.

Unblu Spark CVE-2025-3519

Q: What is the CVSS score of CVE-2025-3519?

CVE-2025-3519 has a CVSS 4.0 base score of 7.0 (High). CVSS vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. EPSS exploitation probability: 0.2%.

HIGH

Authorization Bypass Through User-Controlled Key (CWE-639)

2025-04-22 vulnerability@ncsc.ch

Authentication Bypass

7.0

CVSS 4.0 · NVD

Severity by source

NVD PRIMARY

7.0 HIGH

CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Attack Vector

Network

Attack Complexity

High

Privileges Required

Low

User Interaction

None

Scope

Lifecycle Timeline

Analysis Generated

Mar 28, 2026 - 18:38 vuln.today

CVE Published

Apr 22, 2025 - 09:15 nvd

HIGH 7.0

DescriptionCVE.org

An authorization bypass in Unblu Spark allows a participant of a conversation to replace an existing, uploaded file.

Every uploaded file in Unblu gets assigned with a randomly generated Universally Unique ID (UUID). In case a participant of this or another conversation gets access to such a file ID, it can be used to replace the file without changing the file name and details or the name of the user who uploaded the file. During the upload, file interception and allowed file type rules are still applied correctly.

AnalysisAI

An authorization bypass in Unblu Spark allows a participant of a conversation to replace an existing, uploaded file. Rated high severity (CVSS 7.0), this vulnerability is remotely exploitable. No vendor patch available.

Technical ContextAI

This vulnerability is classified under CWE-639. An authorization bypass in Unblu Spark allows a participant of a conversation to replace an existing, uploaded file. Every uploaded file in Unblu gets assigned with a randomly generated Universally Unique ID (UUID). In case a participant of this or another conversation gets access to such a file ID, it can be used to replace the file without changing the file name and details or the name of the user who uploaded the file. During the upload, file interception and allowed file type rules are still applied correctly.

Affected ProductsAI

Unblu Spark.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.