CVE-2020-2504 | Absolute path traversal vulnerability in QES

If exploited, this absolute path traversal vulnerability could allow attackers to traverse files in File Station. QNAP has already fixed these issues in QES 2.1.1 Build 20201006 and later.

Published: 2020-12-24 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2020-2504 is rated Moderate Risk (41.9/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.35%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2020-2504

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-03-30 0.68% 0.35% -0.33%
2 2025-03-29 0.30% 0.68% +0.38%
3 2025-03-17 — 0.30% —

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-2504

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.8 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 1.4 [email protected]
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 3.6 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:P/I:N/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
 10.0 2.9 [email protected]

Weakness enumeration for CVE-2020-2504

Affected software / configurations for CVE-2020-2504

Vendor Product Version Raw CPE
qnap qes < 2.1.1 cpe:2.3:a:qnap:qes:*:*:*:*:*:*:*:*
qnap qes 2.1.1 cpe:2.3:a:qnap:qes:2.1.1:-:*:*:*:*:*:*
qnap qes 2.1.1 cpe:2.3:a:qnap:qes:2.1.1:build_20200211:*:*:*:*:*:*
qnap qes 2.1.1 cpe:2.3:a:qnap:qes:2.1.1:build_20200303:*:*:*:*:*:*
qnap qes 2.1.1 cpe:2.3:a:qnap:qes:2.1.1:build_20200319:*:*:*:*:*:*
qnap qes 2.1.1 cpe:2.3:a:qnap:qes:2.1.1:build_20200424:*:*:*:*:*:*
qnap qes 2.1.1 cpe:2.3:a:qnap:qes:2.1.1:build_20200515:*:*:*:*:*:*
qnap qes 2.1.1 cpe:2.3:a:qnap:qes:2.1.1:build_20200811:*:*:*:*:*:*

References for CVE-2020-2504

cvelogic Threat Intelligence