CVE-2020-2503 - CVE House
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Status published Critical CVE-2020-2503

Stored cross-site scripting vulnerability in QES

Vulnerability Description

If exploited, this stored cross-site scripting vulnerability could allow remote attackers to inject malicious code in File Station. QNAP has already fixed these issues in QES 2.1.1 Build 20201006 and later.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

  • TIM Security Red Team Research

References

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Affected Vendor

QNAP Systems Inc.

View all reports →

Affected Software

QES
Vulnerable Versions:
unspecified

Timeline

Official Publish: December 24th, 2020
Last Modified: September 17th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H

Weaknesses (CWE)

CWE-79 CWE-80 CWE-749

MITRE ATT&CK TTPs

T1189 Drive-by Compromise
Initial Access
T1059.007 JavaScript
Execution
T1539 Steal Web Session Cookie
Collection
T1213 Data from Information Repositories
Collection
T1567 Exfiltration Over Web Service
Exfiltration
T1491.001 Defacement
Impact
T1059 Command and Scripting Interpreter
Execution
T1552 Unsecured Credentials
Credential Access
T1071 Application Layer Protocol
Command and Control
T1565 Data Manipulation
Impact
T1190 Exploit Public-Facing Application
Initial Access
T1068 Exploitation for Privilege Escalation
Privilege Escalation
T1565.002 Stored Data Manipulation
Impact