CVE-2021-43584

Exp

DOM-based Cross Site Scripting (XSS vulnerability in 'Tail Event Logs' functionality in Nagios Nagios Cross-Platform Agent (NCPA) before 2.4.0 allows attackers to run arbitrary code via the name element when filtering for a log.

Published: 2024-01-24 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2021-43584 is rated Exploit Available (57.5/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 1.20%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2021-43584

EDB-ID Source Kind Published Link
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2021-43584

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.34% 1.20% +0.86%
2 2025-11-21 12.10% 0.34% -11.76%
3 2025-11-18 12.10%

Full EPSS history (9 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-43584

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.8 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:H)
They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
1.7 2.7 [email protected]
4.8 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:H)
They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
1.7 2.7 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2021-43584

Affected software / configurations for CVE-2021-43584

Vendor Product Version Raw CPE
nagios nagios_cross_platform_agent < 2.4.0 cpe:2.3:a:nagios:nagios_cross_platform_agent:*:*:*:*:*:*:*:*

References for CVE-2021-43584

URL Tags
https://github.com/NagiosEnterprises/ncpa/issues/830 Exploit Issue Tracking Third Party Advisory
cvelogic Threat Intelligence