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Fencer Intel
medium 4.8

CVE-2021-21494 json

MK-AUTH through 19.01 K4.9 allows XSS via the admin/logs_ajax.php tipo parameter.

published 5y ago modified 4mo ago also EUVD-2021-8767

cvss
4.8
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.5%
EPSS 0.5% chance of exploitation in 30 days, percentile 44%
public exploits
0
none known

Summary

MK-AUTH through 19.01 K4.9 allows XSS via the admin/logs_ajax.php tipo parameter. An attacker can leverage this to read the centralmka2 (session token) cookie, which is not set to HTTPOnly.

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Exploit prediction

0.52% chance of exploitation in the next 30 days, higher than 44% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • gist.github.com https://gist.github.com/alacerda/380b8923e36a29a02ba1457c1eb3ec2f referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 3.1 4.8 CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
NVD 2.0 3.5 AV:N/AC:M/Au:S/C:N/I:P/A:N

Classification

Weakness
  • CWE-732 Incorrect Permission Assignment for Critical Resource

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.