How severe is CVE-2021-41282?

CVE-2021-41282 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-41282 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 87% (100th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-41282?

CVE-2021-41282 affects Pfsense. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-41282?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-41282 published?

CVE-2021-41282 was published on 2022-03-01 and last updated on 2026-06-17.

CVE-2021-41282

CVE-2021-41282 is a high-severity vulnerability in Pfsense with a CVSS 3.x base score of 8.8. Its EPSS exploit-prediction score of 87% places it in the 100th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-74.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 9.0
EPSS exploit prediction: 87% (100th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-74
Affected product: Pfsense
Published: 2022-03-01
Last modified: 2026-06-17

Description

diag_routes.php in pfSense 2.5.2 allows sed data injection. Authenticated users are intended to be able to view data about the routes set in the firewall. The data is retrieved by executing the netstat utility, and then its output is parsed via the sed utility. Although the common protection mechanisms against command injection (i.e., the usage of the escapeshellarg function for the arguments) are used, it is still possible to inject sed-specific code and write an arbitrary file in an arbitrary location.

Frequently asked questions

What is CVE-2021-41282?: diag_routes.php in pfSense 2.5.2 allows sed data injection. Authenticated users are intended to be able to view data about the routes set in the firewall. The data is retrieved by executing the netstat utility, and then its output is parsed via the sed utility. Although the common protection mechanisms against command injection (i.e., the usage of the escapeshellarg function for the arguments) are used, it is still possible to inject sed-specific code and write an arbitrary file in an arbitrary location.
How severe is CVE-2021-41282?: CVE-2021-41282 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-41282 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 87% (100th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-41282?: CVE-2021-41282 affects Pfsense. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-41282?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-41282 published?: CVE-2021-41282 was published on 2022-03-01 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:pfsense:pfsense:2.5.2:*:*:*:*:*:*:*

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