How severe is CVE-2020-8515?

CVE-2020-8515 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-8515 being actively exploited?

Yes. CVE-2020-8515 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2021-11-03, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2020-8515?

CVE-2020-8515 primarily affects Draytek Vigor2960 Firmware. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-8515?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2020-8515 have an EU (EUVD) identifier?

Yes. CVE-2020-8515 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2020-29381. It is also flagged as exploited in the EUVD (since 2021-11-03).

When was CVE-2020-8515 published?

CVE-2020-8515 was published on 2020-02-01 and last updated on 2026-06-17.

CVE-2020-8515

CVE-2020-8515 is a critical-severity vulnerability in Draytek Vigor2960 Firmware with a CVSS 3.x base score of 9.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2021-11-03). The underlying weakness is classified as CWE-78.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 10.0
EPSS exploit prediction: 100% (100th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2021-11-03)
EU (EUVD) id: EUVD-2020-29381
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2021-11-03)
Weakness: CWE-78
Affected product: Draytek Vigor2960 Firmware
Published: 2020-02-01
Last modified: 2026-06-17

Description

DrayTek Vigor2960 1.3.1_Beta, Vigor3900 1.4.4_Beta, and Vigor300B 1.3.3_Beta, 1.4.2.1_Beta, and 1.4.4_Beta devices allow remote code execution as root (without authentication) via shell metacharacters to the cgi-bin/mainfunction.cgi URI. This issue has been fixed in Vigor3900/2960/300B v1.5.1.

Frequently asked questions

What is CVE-2020-8515?: DrayTek Vigor2960 1.3.1_Beta, Vigor3900 1.4.4_Beta, and Vigor300B 1.3.3_Beta, 1.4.2.1_Beta, and 1.4.4_Beta devices allow remote code execution as root (without authentication) via shell metacharacters to the cgi-bin/mainfunction.cgi URI. This issue has been fixed in Vigor3900/2960/300B v1.5.1.
How severe is CVE-2020-8515?: CVE-2020-8515 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-8515 being actively exploited?: Yes. CVE-2020-8515 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2021-11-03, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2020-8515?: CVE-2020-8515 primarily affects Draytek Vigor2960 Firmware. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-8515?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2020-8515 have an EU (EUVD) identifier?: Yes. CVE-2020-8515 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2020-29381. It is also flagged as exploited in the EUVD (since 2021-11-03).
When was CVE-2020-8515 published?: CVE-2020-8515 was published on 2020-02-01 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:o:draytek:vigor2960_firmware:1.3.1:beta:*:*:*:*:*:*
cpe:2.3:o:draytek:vigor300b_firmware:1.3.3:beta:*:*:*:*:*:*
cpe:2.3:o:draytek:vigor300b_firmware:1.4.2.1:beta:*:*:*:*:*:*
cpe:2.3:o:draytek:vigor300b_firmware:1.4.4:beta:*:*:*:*:*:*
cpe:2.3:o:draytek:vigor3900_firmware:1.4.4:beta:*:*:*:*:*:*

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