CVE-2021-43556

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

2.22% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 82.5% 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

2021-12-28 18:17Z4 YR AGO

Last updated

2024-09-16 20:01Z2 YR AGO

Reserved

2021-11-08

Assigning CNA

icscert

Record state

PUBLISHED

Severity

High (CVSS 7.8)

CNA CVSS vector

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

Weaknesses

• CWE-121Stack-based Buffer OverflowVariant
• CWE-787Out-of-bounds WriteBase

Data version

5.1

Document digest

9c50a8c444cc0817cab1ae028c3e13b5336e5c580e9e162d618e0d95949e35c2

• us-cert.cisa.govhttps://us-cert.cisa.gov/ics/advisories/icsa-21-320-01x_refsource_MISC
• www.zerodayinitiative.comhttps://www.zerodayinitiative.com/advisories/ZDI-22-029/x_refsource_MISC
• www.zerodayinitiative.comhttps://www.zerodayinitiative.com/advisories/ZDI-22-032/x_refsource_MISC
• www.zerodayinitiative.comhttps://www.zerodayinitiative.com/advisories/ZDI-22-031/x_refsource_MISC