CVE-2021-34423

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

3.21% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 87.0% 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

2021-11-24 16:53Z4 YR AGO

Last updated

2024-09-17 03:23Z1 YR AGO

Reserved

2021-06-09

Assigning CNA

Zoom

Record state

PUBLISHED

Severity

High (CVSS 7.3)

CNA CVSS vector

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

Weaknesses

• CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')Base

Data version

5.1

Document digest

7bc1859816c0513d6d0d5d0ba4c97944d8a9ccbe4c7eadce62e99cb46d343596

• explore.zoom.ushttps://explore.zoom.us/en/trust/security/security-bulletinx_refsource_MISC
• packetstormsecurity.comhttp://packetstormsecurity.com/files/165417/Zoom-Chat-Message-Processing-Buffer-Overflow.htmlx_refsource_MISC