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Fencer Intel
medium 6.1

CVE-2021-3243 json

Wfilter ICF 5.0.117 contains a cross-site scripting (XSS) vulnerability.

published 5y ago modified 4mo ago also EUVD-2021-26582

cvss
6.1
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.7%
EPSS 0.7% chance of exploitation in 30 days, percentile 54%
public exploits
0
none known

Summary

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 through its plugin-running function.

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Exploit prediction

0.73% chance of exploitation in the next 30 days, higher than 54% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • drivertom.blogspot.com https://drivertom.blogspot.com/2021/01/wfilter-icf-0day-rce.html referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 3.1 6.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
NVD 2.0 4.3 AV:N/AC:M/Au:N/C:N/I:P/A:N

Classification

Weakness
  • CWE-79 Improper Neutralization of Input During Web Page Generation

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.