CVE-2020-21487

criticalpriority · track · 38EPSS 0.007 · 52 %ileDEEUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

0.67% (52nd) EPSS

CVSS 9.6 · critical

Is it mine?

4 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · cert_bund · nvd

EPSS · scored 2026-10-27

Cross Site Scripting vulnerability found in Netgate pfSense 2.4.4 and ACME package v.0.6.3 allows attackers to execute arbitrary code via the RootFolder field of acme_certificates.php.

cvss

Technical severity, 0–10. One row per scoring source.

9.6

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 8.8–9.6

v3.19.6criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 6

v3.19.6criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:Hsecondary · ENISA EU

v3.19.6criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:Hsecondaryexploitability 2.8 · impact 6

v3.18.8highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-79USprimary

affected products (4)

Products and version ranges known to be affected.

Netgate pfSense 2.4.4all versionscert_bundDEcpe:/a:netgate:pfsense:2.4.4:-
n/a n/a≤ n/aenisa_euvdEU
netgate pfsense= 2.4.4nvdUScpe:2.3:a:netgate:pfsense:*:*:*:*:*:*:*:*
netgate pfsense acme package= 0.6.3nvdUScpe:2.3:a:netgate:pfsense_acme_package:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2023-0846Netgate pfSense: Schwachstelle ermöglicht Cross-Site ScriptingDeutsch2023-04-04csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann eine Schwachstelle in Netgate pfSense ausnutzen, um einen Cross-Site Scripting Angriff durchzuführen.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cert_bund nvd NVD CVE.org MITRE

published 2023-04-04modified 2026-06-17

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An issue was discovered in Zimbra Collaboration (ZCS) 8.8.15 and 9.0 and 10.0 and 10.1. A Cross-Site Scripting (XSS) vulnerability in the Zimbra Classic UI allows attackers to exec…
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+53058 more

references (7)

External citations — patches, advisories, analysis.

scry

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