CVE-2021-27239

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

0.75% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 52.2% of scored records. A rank, not a probability.

NVD base score

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

NVD CVSS vector

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/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

2021-03-29 21:05Z5 YR AGO

Last updated

2024-08-03 20:48Z2 YR AGO

Reserved

2021-02-16

Assigning CNA

zdi

Record state

PUBLISHED

Severity

High (CVSS 8.8)

CNA CVSS vector

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

Weaknesses

• CWE-121Stack-based Buffer OverflowVariant

Data version

5.1

Document digest

8ed5cac19ad86157f1bf5e26b6df23ca26845318bec67d4dcebdcb1f56dcd89f

• www.zerodayinitiative.comhttps://www.zerodayinitiative.com/advisories/ZDI-21-206/x_refsource_MISC
• kb.netgear.comhttps://kb.netgear.com/000062820/Security-Advisory-for-Stack-based-Buffer-Overflow-Remote-Code-Execution-Vulnerability-on-Some-Routers-PSV-2020-0432x_refsource_MISC