Bytedesk up to 1.3.9 SVG File UploadRestService.java handleFileUpload unrestricted upload

CVSS Meta Temp Score
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CTI Interest Score
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6.9$0-$5k0.00

Summaryinfo

A vulnerability was found in Bytedesk up to 1.3.9. It has been rated as critical. This issue affects the function handleFileUpload of the file source-code/src/main/java/com/bytedesk/core/upload/UploadRestService.java of the component SVG File Handler. The manipulation leads to unrestricted upload. This vulnerability is uniquely identified as CVE-2026-3749. The attack is possible to be carried out remotely. Moreover, an exploit is present. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Bytedesk up to 1.3.9 and classified as critical. This issue affects the function handleFileUpload of the file source-code/src/main/java/com/bytedesk/core/upload/UploadRestService.java of the component SVG File Handler. The manipulation with an unknown input leads to a unrestricted upload vulnerability. Using CWE to declare the problem leads to CWE-434. The product allows the attacker to upload or transfer files of dangerous types that can be automatically processed within the product's environment. Impacted is confidentiality, integrity, and availability.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-3749. The exploitation is known to be easy. The attack may be initiated remotely. Technical details as well as a public exploit are known. The attack technique deployed by this issue is T1608.002 according to MITRE ATT&CK.

The exploit is available at github.com. It is declared as proof-of-concept.

Upgrading to version 1.4.5.1 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch 975e39e4dd527596987559f56c5f9f973f64eff7 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-10252). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 7.1
VulDB Meta Temp Score: 6.9

VulDB Base Score: 6.3
VulDB Temp Score: 5.7
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 8.8
NVD Vector: 🔒

CNA Base Score: 6.3
CNA Vector: 🔒

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Unrestricted upload
CWE: CWE-434 / CWE-284 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Access: Public
Status: Proof-of-Concept
Download: 🔒

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Bytedesk 1.4.5.1
Patch: 975e39e4dd527596987559f56c5f9f973f64eff7

Timelineinfo

03/07/2026 Advisory disclosed
03/07/2026 +0 days VulDB entry created
03/12/2026 +5 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: 19
Status: Confirmed
Confirmation: 🔒

CVE: CVE-2026-3749 (🔒)
GCVE (CVE): GCVE-0-2026-3749
GCVE (VulDB): GCVE-100-349727
EUVD: 🔒
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 03/07/2026 21:28
Updated: 03/12/2026 16:36
Changes: 03/07/2026 21:28 (63), 03/08/2026 18:40 (1), 03/08/2026 19:48 (30), 03/12/2026 16:36 (12)
Complete: 🔍
Submitter: ZAST.AI
Cache ID: 216:762:103

Submitinfo

Accepted

  • Submit #768030: Bytedesk <=1.3.9 Unrestricted Upload of File with Dangerous Type (CWE-434) (by ZAST.AI)

Be aware that VulDB is the high quality source for vulnerability data.

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