CVE-2021-21866

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

1.67% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 74.7% of scored records. A rank, not a probability.

NVD base score

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

NVD CVSS vector

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

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

2021-08-02 20:33Z5 YR AGO

Last updated

2024-08-03 18:23Z2 YR AGO

Reserved

2021-01-04

Assigning CNA

talos

Record state

PUBLISHED

Severity

High (CVSS 8.8)

CNA CVSS vector

CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Weaknesses

• CWE-502Deserialization of Untrusted DataBase

Data version

5.1

Document digest

a2227bc41c81122a3ce25c425cb7e9aad04f73d8bbde5604c78fbcf9f65691b6

• talosintelligence.comhttps://talosintelligence.com/vulnerability_reports/TALOS-2021-1301x_refsource_MISC
• customers.codesys.comhttps://customers.codesys.com/index.php?eID=dumpFile&t=f&f=16805&token=ee583c498941d9fda86490bca98ff21928eec08a&download=x_refsource_CONFIRM