Mfscripts YetiShare File Hosting Script 5.1.0 URL Parameter url_upload_handler url unrestricted upload

CVSS Meta Temp Score
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CTI Interest Score
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5.3$0-$5k0.00

Summaryinfo

A vulnerability described as critical has been identified in Mfscripts YetiShare File Hosting Script 5.1.0. This issue affects the function url_upload_handler of the component URL Parameter Handler. Executing a manipulation of the argument url can lead to unrestricted upload. This vulnerability is handled as CVE-2021-47899. The attack can be executed remotely. Additionally, an exploit exists.

Detailsinfo

A vulnerability classified as critical was found in Mfscripts YetiShare File Hosting Script 5.1.0. This vulnerability affects the function url_upload_handler of the component URL Parameter Handler. The manipulation of the argument url with an unknown input leads to a unrestricted upload vulnerability. The CWE definition for the vulnerability is 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. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

YetiShare File Hosting Script 5.1.0 contains a server-side request forgery vulnerability that allows attackers to read local system files through the remote file upload feature. Attackers can exploit the url parameter in the url_upload_handler endpoint to access sensitive files like /etc/passwd by using file:/// protocol.

The weakness was released by Numan Türle as 49534. The advisory is shared for download at exploit-db.com. This vulnerability was named CVE-2021-47899 since 01/18/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Technical details and also a public exploit are known. The MITRE ATT&CK project declares the attack technique as T1608.002.

It is possible to download the exploit at exploit-db.com. It is declared as proof-of-concept.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at Exploit-DB (49534) and EUVD (EUVD-2026-4304). Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

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Version

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: 5.7
VulDB Meta Temp Score: 5.3

VulDB Base Score: 7.3
VulDB Temp Score: 6.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 4.0
CNA Vector (VulnCheck): 🔒

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: Partially
Local: Yes
Remote: Yes

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

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Exploit-DB: 🔒

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

01/18/2026 CVE reserved
01/23/2026 +5 days Advisory disclosed
01/23/2026 +0 days VulDB entry created
01/24/2026 +1 days VulDB entry last update

Sourcesinfo

Advisory: 49534
Researcher: Numan Türle
Status: Not defined

CVE: CVE-2021-47899 (🔒)
GCVE (CVE): GCVE-0-2021-47899
GCVE (VulDB): GCVE-100-342676
EUVD: 🔒
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 01/23/2026 18:38
Updated: 01/24/2026 09:56
Changes: 01/23/2026 18:38 (82), 01/24/2026 09:56 (1)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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