# Open-Xchange Dovecot vulnerabilities

Source: https://junglewise.ai/threats/technologies/open-xchange-dovecot  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Updated: 9 November 2026, 03:07 UTC. Rebuilt every hour.  
Data: https://junglewise.ai/threats/technologies/open-xchange-dovecot.json  
License: CC BY 4.0 with a link back

Junglewise Threat Intelligence has tracked 5 vulnerabilities in Open-Xchange Dovecot: 0 in the last 7 days and 0 in the last 90 days, 0 of them critical and 0 exploited in the wild. The most recent, CVE-2026-27860, was published on 27 March 2026.

## Counts

- Last 7 days: 0
- Last 30 days: 0
- Last 90 days: 0
- All time: 5 (0 critical, 0 exploited in the wild)

## About Open-Xchange Dovecot

Open-source mail server software providing IMAP and POP3 access protocols.

## Latest Open-Xchange Dovecot vulnerabilities

- [CVE-2026-27860: If auth_username_chars is empty, it is possible to inject arbitrary LDAP filter to Dovecot's LDAP authentication. This…](https://junglewise.ai/threats/cve-2026-27860-if-auth-username-chars-is-empty-it-is-possible-to-inject) (low, CVSS 3.7, published 27 Mar 2026)
- [CVE-2026-27859: A mail message containing excessive amount of RFC 2231 MIME parameters causes LMTP to use too much CPU. A suitably…](https://junglewise.ai/threats/cve-2026-27859-a-mail-message-containing-excessive-amount-of-rfc-2231-mime) (medium, CVSS 5.3, published 27 Mar 2026)
- [CVE-2026-27855: Dovecot OTP authentication is vulnerable to replay attack under specific conditions. If auth cache is enabled, and…](https://junglewise.ai/threats/cve-2026-27855-dovecot-otp-authentication-is-vulnerable-to-replay-attack-under) (medium, CVSS 6.8, published 27 Mar 2026)
- [CVE-2026-0394: When dovecot has been configured to use per-domain passwd files, and they are placed one path component above /etc, or…](https://junglewise.ai/threats/cve-2026-0394-when-dovecot-has-been-configured-to-use-per-domain-passwd-files) (medium, CVSS 5.3, published 27 Mar 2026)
- [CVE-2025-59028: When sending invalid base64 SASL data, login process is disconnected from the auth server, causing all active…](https://junglewise.ai/threats/cve-2025-59028-when-sending-invalid-base64-sasl-data-login-process-is) (medium, CVSS 5.3, published 27 Mar 2026)

## Most severe Open-Xchange Dovecot vulnerabilities

- [CVE-2026-27855: Dovecot OTP authentication is vulnerable to replay attack under specific conditions. If auth cache is enabled, and…](https://junglewise.ai/threats/cve-2026-27855-dovecot-otp-authentication-is-vulnerable-to-replay-attack-under) (medium, CVSS 6.8, published 27 Mar 2026)
- [CVE-2025-59028: When sending invalid base64 SASL data, login process is disconnected from the auth server, causing all active…](https://junglewise.ai/threats/cve-2025-59028-when-sending-invalid-base64-sasl-data-login-process-is) (medium, CVSS 5.3, published 27 Mar 2026)
- [CVE-2026-0394: When dovecot has been configured to use per-domain passwd files, and they are placed one path component above /etc, or…](https://junglewise.ai/threats/cve-2026-0394-when-dovecot-has-been-configured-to-use-per-domain-passwd-files) (medium, CVSS 5.3, published 27 Mar 2026)
- [CVE-2026-27859: A mail message containing excessive amount of RFC 2231 MIME parameters causes LMTP to use too much CPU. A suitably…](https://junglewise.ai/threats/cve-2026-27859-a-mail-message-containing-excessive-amount-of-rfc-2231-mime) (medium, CVSS 5.3, published 27 Mar 2026)
- [CVE-2026-27860: If auth_username_chars is empty, it is possible to inject arbitrary LDAP filter to Dovecot's LDAP authentication. This…](https://junglewise.ai/threats/cve-2026-27860-if-auth-username-chars-is-empty-it-is-possible-to-inject) (low, CVSS 3.7, published 27 Mar 2026)

## Vulnerabilities per week

Nothing was published in the last eight weeks.

| Week of | Vulns | Critical | Exploited |
| --- | --- | --- | --- |
| 17 Aug 2026 | 0 | 0 | 0 |
| 24 Aug 2026 | 0 | 0 | 0 |
| 31 Aug 2026 | 0 | 0 | 0 |
| 7 Sep 2026 | 0 | 0 | 0 |
| 14 Sep 2026 | 0 | 0 | 0 |
| 21 Sep 2026 | 0 | 0 | 0 |
| 28 Sep 2026 | 0 | 0 | 0 |
| 5 Oct 2026 | 0 | 0 | 0 |
| 12 Oct 2026 | 0 | 0 | 0 |
| 19 Oct 2026 | 0 | 0 | 0 |
| 26 Oct 2026 | 0 | 0 | 0 |
| 2 Nov 2026 | 0 | 0 | 0 |
| 9 Nov 2026 | 0 | 0 | 0 |

## Other Open-Xchange technologies

- [Open-Xchange Dovecot Pro](https://junglewise.ai/threats/technologies/dovecot-pro): 28 vulnerabilities
- [Open-Xchange Dovecot CE](https://junglewise.ai/threats/technologies/dovecot-ce): 8 vulnerabilities

## Sources

NVD, GitHub Security Advisories, OSV, the CISA Known Exploited Vulnerabilities catalog, FIRST EPSS and vendor advisories. Rebuilt every hour. Cite as: Junglewise Threat Intelligence, "Open-Xchange Dovecot vulnerabilities", https://junglewise.ai/threats/technologies/open-xchange-dovecot, 9 November 2026.