CVE-2020-2503
CVE-2020-2503 is a critical-severity vulnerability in Qnap Qes with a CVSS 3.x base score of 9.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.
Key facts
- Severity: Critical (CVSS 3.x base score 9.0)
- CVSS v2: 3.5
- EPSS exploit prediction: 1% (51st percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-79
- Affected product: Qnap Qes
- Published:
- Last modified:
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.
Frequently asked questions
- What is CVE-2020-2503?
- 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.
- How severe is CVE-2020-2503?
- CVE-2020-2503 has a CVSS 3.x base score of 9.0, rated critical severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2020-2503 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-2503?
- CVE-2020-2503 primarily affects Qnap Qes. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2020-2503?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
- When was CVE-2020-2503 published?
- CVE-2020-2503 was published on 2020-12-24 and last updated on 2026-06-17.
References
Affected products (8)
- cpe:2.3:a:qnap:qes:*:*:*:*:*:*:*:*
- cpe:2.3:a:qnap:qes:2.1.1:-:*:*:*:*:*:*
- cpe:2.3:a:qnap:qes:2.1.1:build_20200211:*:*:*:*:*:*
- cpe:2.3:a:qnap:qes:2.1.1:build_20200303:*:*:*:*:*:*
- cpe:2.3:a:qnap:qes:2.1.1:build_20200319:*:*:*:*:*:*
- cpe:2.3:a:qnap:qes:2.1.1:build_20200424:*:*:*:*:*:*
- cpe:2.3:a:qnap:qes:2.1.1:build_20200515:*:*:*:*:*:*
- cpe:2.3:a:qnap:qes:2.1.1:build_20200811:*:*:*:*:*:*
More vulnerabilities in Qnap Qes
- CVE-2020-2499 — Medium (CVSS 6.3): A hard-coded password vulnerability has been reported to affect earlier versions of QES. If exploited, this…
- CVE-2020-2504 — Medium (CVSS 5.8): If exploited, this absolute path traversal vulnerability could allow attackers to traverse files in File Station. QNAP…
- CVE-2020-2505 — Low (CVSS 2.3): If exploited, this vulnerability could allow attackers to gain sensitive information via generation of error messages.…
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