CVE-2021-27189

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

0.99% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 59.9% 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

2021-02-22 23:16Z5 YR AGO

Last updated

2024-08-03 20:40Z2 YR AGO

Reserved

2021-02-10

Assigning CNA

mitre

Record state

PUBLISHED

Severity

Not rated by the issuing CNA

CNA CVSS vector

Not published by the issuing CNA

Weaknesses

• CWE-295Improper Certificate ValidationBase

Data version

5.1

Document digest

02e99d5ccbf13e02c4f27f333935ce1171568e3b2e0abf12389f81111d885e3a

• www.info-sec.cahttps://www.info-sec.ca/advisories/CIRA-Canadian-Shield.htmlx_refsource_MISC
• seclists.org20210223 CIRA Canadian Shield iOS Application - MITM SSL Certificate Vulnerability (CVE-2021-27189)http://seclists.org/fulldisclosure/2021/Feb/72mailing-listx_refsource_FULLDISC
• packetstormsecurity.comhttp://packetstormsecurity.com/files/161507/CIRA-Canadian-Shield-Man-In-The-Middle.htmlx_refsource_MISC