CVE-2021-20729
Cross-site scripting vulnerability in pfSense CE and pfSense Plus (pfSense CE software versions 2...
Cross-site scripting vulnerability in pfSense CE and pfSense Plus (pfSense CE software versions 2.5.2 and earlier, and pfSense Plus software versions 21.05 and earlier) allows a remote attacker to inject an arbitrary script via a malicious URL.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
Cross-site scripting vulnerability in pfSense CE and pfSense Plus (pfSense CE software versions 2.5.2 and earlier, and pfSense Plus software versions 21.05 and earlier) allows a remote attacker to inject an arbitrary script via a malicious URL.
- Record
CVE-2021-20729- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - CVSS 2.0
- 4.3 Medium
AV:N/AC:M/Au:N/C:N/I:P/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
CVE List No score
Cross-site scripting vulnerability in pfSense CE and pfSense Plus (pfSense CE software versions 2.5.2 and earlier, and pfSense Plus software versions 21.05 and earlier) allows a remote attacker to inject an arbitrary script via a malicious URL.
- Record
CVE-2021-20729- Updated
- 2026-11-02
EUVDEUVD-2021-8143 No score
Cross-site scripting vulnerability in pfSense CE and pfSense Plus (pfSense CE software versions 2.5.2 and earlier, and pfSense Plus software versions 21.05 and earlier) allows a remote attacker to inject an arbitrary script via a malicious URL.
- Record
EUVD-2021-8143- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-gmq9-rc2w-2c75
Cross-site scripting vulnerability in pfSense CE and pfSense Plus (pfSense CE software versions 2...
Cross-site scripting vulnerability in pfSense CE and pfSense Plus (pfSense CE software versions 2.5.2 and earlier, and pfSense Plus software versions 21.05 and earlier) allows a remote attacker to inject an arbitrary script via a malicious URL.
- Record
GHSA-gmq9-rc2w-2c75- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
OSV
Cross-site scripting vulnerability in pfSense CE and pfSense Plus (pfSense CE software versions 2.5.2 and earlier, and pfSense Plus software versions 21.05 and earlier) allows a remote attacker to inject an arbitrary script via a malicious URL.
- Record
CVE-2021-20729- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-20729 is a medium vulnerability (CVSS 6.1) in Netgate Pfsense Plus, published March 31, 2022. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 2.88%, the 86th percentile. No source names a fixed version.