CVE-2021-40823

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

0.66% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 49.1% of scored records. A rank, not a probability.

NVD base score

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

NVD CVSS vector

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

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

2021-09-13 18:45Z4 YR AGO

Last updated

2024-08-04 02:51Z2 YR AGO

Reserved

2021-09-09

Assigning CNA

mitre

Record state

PUBLISHED

Severity

Not rated by the issuing CNA

CNA CVSS vector

Not published by the issuing CNA

Weaknesses

• CWE-290Authentication Bypass by SpoofingBase

Data version

5.1

Document digest

1f8d5132f661d336dfd2270bd83ad818a0f8fb8d20abc1c4468b4cd85c01d841

• github.comhttps://github.com/matrix-org/matrix-js-sdk/releases/tag/v12.4.1x_refsource_MISC
• matrix.orghttps://matrix.org/blog/2021/09/13/vulnerability-disclosure-key-sharingx_refsource_MISC