CVE-2021-43991

Exploitation

Not assessed. CISA has not published an exploitation assessment for this record, and it is not in the KEV catalog. That is an absence of assessment, not a finding of no risk.

SSVC decision

Not assessed by CISA

EPSS probability

0.56% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 46.6% of scored records. A rank, not a probability.

NVD base score

5.4 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

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

NVD analysis status

Modified. NVD last modified this record on 2026-06-17.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2021-12-03 14:42Z4 YR AGO

Last updated

2024-08-04 04:10Z2 YR AGO

Reserved

2021-11-17

Assigning CNA

AppCheck

Record state

PUBLISHED

Severity

Medium (CVSS 6.8)

CNA CVSS vector

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

Weaknesses

• CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')Base

Data version

5.1

Document digest

dd89f41657f536bdec7d8dc9f8eb4afdadee6df512161510b4f3d6d6098495d0

• appcheck-ng.comhttps://appcheck-ng.com/persistent-xss-kentico-cms/x_refsource_MISC