Cyber Resilience

CVE-2021-3243

MediumPublic PoC

Published: 15 April 2021

Published
15 April 2021
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 6.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
EPSS Score 0.0022 44.3th percentile
Risk Priority 12 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-3243 is a medium-severity Cross-site Scripting (CWE-79) vulnerability in Wfiltericf Wfilter Internet Content Filter. Its CVSS base score is 6.1 (Medium).

Operationally, ranked at the 44.3th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

Wfilter ICF 5.0.117 contains a cross-site scripting (XSS) vulnerability. An attacker in the same LAN can craft a packet with a malicious User-Agent header to inject a payload in its logs, where an attacker can take over the system by…

more

through its plugin-running function.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

wfiltericf
wfilter internet content filter
5.0.117

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-79

Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.

addresses: CWE-79

Validates web inputs to reject script-related content that could produce XSS.

addresses: CWE-79

Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.

References