CVE-2021-40393

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

3.14% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 87.6% of scored records. A rank, not a probability.

NVD base score

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

NVD CVSS vector

CVSS:3.1/AV:N/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

2021-12-22 00:00Z4 YR AGO

Last updated

2024-08-04 02:44Z2 YR AGO

Reserved

2021-09-01

Assigning CNA

talos

Record state

PUBLISHED

Severity

Critical (CVSS 10.0)

CNA CVSS vector

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

Weaknesses

• CWE-119Improper Restriction of Operations within the Bounds of a Memory BufferClass
• CWE-787Out-of-bounds WriteBase

Data version

5.1

Document digest

435f6951a4a1f21240a7f7c42452ac326d4f222d2762e7040ba6df308eb6616c

• talosintelligence.comhttps://talosintelligence.com/vulnerability_reports/TALOS-2021-1404
• www.debian.orgDSA-5306https://www.debian.org/security/2022/dsa-5306vendor-advisory
• lists.fedoraproject.orgFEDORA-2023-5f5bea627bhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/37OSNNO5N5FJZP6ZBYRJMML5HYMJQIX7/vendor-advisory
• lists.debian.org[debian-lts-announce] 20230930 [SECURITY] [DLA 3593-1] gerbv security updatehttps://lists.debian.org/debian-lts-announce/2023/09/msg00040.htmlmailing-list