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NVD / CVE Program· CNA mitre

CVE-2021-41282: diag_routes.php in pfSense 2.5.2 allows sed data injection.

Noroxi assessment

Priority: This week (action score 61/100)

  • A ready-made attack module is public (Metasploit, Nuclei); exploiting it takes no special expertise.
  • Probability of exploitation in the next 30 days: 87.1% (FIRST EPSS); higher than 99.7% of all records.
  • Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • According to the record, no fixed version is available yet.

Don’t wait for the next maintenance window. Until a fix is released, restrict access to the affected component and follow the vendor's advisory.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

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.

HighCVSS 8.8 · v3.1—Weaponized No fix recorded
Published
Mar 1, 2022
Updated
Jun 17, 2026
EPSS
87.1% · 99th percentile

Report tools

JSON

Action score

61

This week

Don’t wait for the next maintenance window.

CVSS
35 / 40 · 8.8 / 10
CISA KEV
0 / 30 · Not listed
EPSS
26 / 30 · 87.1%

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • Weaponized exploit exists
  • No fixed version yet

If any of these changes, we'll tell you in the daily email digest.

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When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
pfsensepfsense

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • pfsense pfsense2.5.2

Same product

pfsense: all records

Other highest-scoring records for the same primary product.

  • CVE-2016-10709pfSense before 2.3 allows remote authenticated users to execute arbitrary OS commands via a '|' character in the status_rrd_graph_img.php gr
    45Plan
  • CVE-2023-29974An issue discovered in Pfsense CE version 2.6.0 allows attackers to compromise user accounts via weak password requirements.
    40Plan
  • CVE-2025-69691Netgate pfSense CE 2.8.0 allows code execution in the XMLRPC API via pfsense.exec_php.
    39Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2020-26693Jun 1, 2021 · A stored cross-site scripting (XSS) vulnerability was discovered in pfSense 2.4.5-p1 which allows an authenticated attacker to execute arbit
    23Monitor
  • ← EarlierCVE-2022-23993Jan 26, 2022 · /usr/local/www/pkg.php in pfSense CE before 2.6.0 and pfSense Plus before 22.01 uses $_REQUEST['pkg_filter'] in a PHP echo call, causing XSS
    24Monitor
  • Later →CVE-2021-20729Mar 31, 2022 · Cross-site scripting vulnerability in pfSense CE and pfSense Plus (pfSense CE software versions 2.5.2 and earlier, and pfSense Plus software
    25Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

No fix version is recorded for this entry. Check the references for vendor advisories.

Exploit status

Weaponized

A ready exploit tool or active in-the-wild use is known for this vulnerability. This should be your top priority.

Evidence

  • Metasploit module ×1
  • Nuclei detection template ×1

Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.

Public exploit evidence
SourceKindDate
Nuclei detection templateNuclei template CVE-2021-41282 —
Metasploit moduleexploit/unix/http/pfsense_diag_routes_webshellpfSense Diag Routes Web Shell Uploadexploit2022-02-23

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

  1. Metasploit-7 d
  2. Published
  3. TodayOct 26, 2026+1700 d
EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-74 · Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Change log

No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.

References

Show all references (1 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records