CVE-2021-26911

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

1.09% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 63.0% of scored records. A rank, not a probability.

NVD base score

7.4 (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:H/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

2021-02-17 20:54Z5 YR AGO

Last updated

2024-08-03 20:33Z2 YR AGO

Reserved

2021-02-08

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

d6c957428faf48508ef1678f7089e713b7371037e803f981a40825f144f7cb0a

• apps.apple.comhttps://apps.apple.com/us/app/canary-mail/id1236045954x_refsource_MISC
• census-labs.comhttps://census-labs.com/news/category/advisories/x_refsource_MISC
• www.openwall.comhttps://www.openwall.com/lists/oss-security/2021/02/17/3x_refsource_MISC
• census-labs.comhttps://census-labs.com/news/2021/02/17/canary-mail-app-missing-certificate-validation-check-on-imap-starttls/x_refsource_MISC
• github.comhttps://github.com/canarymail/mailcore2/commit/45acb4efbcaa57a20ac5127dc976538671fce018x_refsource_CONFIRM
• www.openwall.com[oss-security] 20210217 CVE-2021-26911: Canary Mail with IMAP STARTTLS missing certificate validationhttp://www.openwall.com/lists/oss-security/2021/02/17/3mailing-listx_refsource_MLIST