# CVE-2026-27851: dovecot: When safe filter is used with variable expansion, all following pipelines on the same string are incorrectly interpre...

CVE-2026-27851 is fixed in 17 products on 1 platform, first by dovecot-auth-lua 1:2.4.1+dfsg1-5ubuntu4.2, released May 12, 2026. It is not reported as exploited. Patch Radar priority: Urgent.

- Web page: https://patchblox.com/security/cve/CVE-2026-27851
- Priority: Urgent
- CVSS: 9.1 (critical)
- EPSS: 0.0041
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: May 12, 2026

## Description

When safe filter is used with variable expansion, all following pipelines on the same string are incorrectly interpreted as safe too, enabling unsafe data to be unescaped. This can enable SQL / LDAP injection attacks when used in authentication. Avoid using safe filter until on fixed version. No publicly available exploits are known.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | dovecot Debian 13.5 (trixie) | 1:2.4.1+dfsg1-6+deb13u6 | [DEBIAN-CVE-2026-27851](https://patchblox.com/security/data/fix/linux/debian-cve-2026-27851.md) | May 27, 2026 |
| Linux | dovecot Debian 14 | 1:2.4.4+dfsg1-1 | [DEBIAN-CVE-2026-27851](https://patchblox.com/security/data/fix/linux/debian-cve-2026-27851.md) | May 27, 2026 |
| Linux | dovecot-auth-lua Ubuntu 25.10 (questing) | 1:2.4.1+dfsg1-5ubuntu4.2 | [dovecot-auth-lua 1:2.4.1+dfsg1-5ubuntu4.2](https://patchblox.com/security/data/fix/linux/ubuntu-questing-dovecot-auth-lua-1-2.4.1-dfsg1-5ubuntu4.2.md) | May 12, 2026 |
| Linux | dovecot-auth-lua Ubuntu 26.04.1 LTS (resolute) | 1:2.4.2+dfsg1-3ubuntu2.1 | [dovecot-auth-lua 1:2.4.2+dfsg1-3ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-dovecot-auth-lua-1-2.4.2-dfsg1-3ubuntu2.1.md) | May 12, 2026 |
| Linux | dovecot-core Ubuntu 25.10 (questing) | 1:2.4.1+dfsg1-5ubuntu4.2 | [dovecot-core 1:2.4.1+dfsg1-5ubuntu4.2](https://patchblox.com/security/data/fix/linux/ubuntu-questing-dovecot-core-1-2.4.1-dfsg1-5ubuntu4.2.md) | May 12, 2026 |
| Linux | dovecot-core Ubuntu 26.04.1 LTS (resolute) | 1:2.4.2+dfsg1-3ubuntu2.1 | [dovecot-core 1:2.4.2+dfsg1-3ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-dovecot-core-1-2.4.2-dfsg1-3ubuntu2.1.md) | May 12, 2026 |
| Linux | dovecot-flatcurve Ubuntu 25.10 (questing) | 1:2.4.1+dfsg1-5ubuntu4.2 | [dovecot-flatcurve 1:2.4.1+dfsg1-5ubuntu4.2](https://patchblox.com/security/data/fix/linux/ubuntu-questing-dovecot-flatcurve-1-2.4.1-dfsg1-5ubuntu4.2.md) | May 12, 2026 |
| Linux | dovecot-flatcurve Ubuntu 26.04.1 LTS (resolute) | 1:2.4.2+dfsg1-3ubuntu2.1 | [dovecot-flatcurve 1:2.4.2+dfsg1-3ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-dovecot-flatcurve-1-2.4.2-dfsg1-3ubuntu2.1.md) | May 12, 2026 |
| Linux | dovecot-gssapi Ubuntu 25.10 (questing) | 1:2.4.1+dfsg1-5ubuntu4.2 | [dovecot-gssapi 1:2.4.1+dfsg1-5ubuntu4.2](https://patchblox.com/security/data/fix/linux/ubuntu-questing-dovecot-gssapi-1-2.4.1-dfsg1-5ubuntu4.2.md) | May 12, 2026 |
| Linux | dovecot-gssapi Ubuntu 26.04.1 LTS (resolute) | 1:2.4.2+dfsg1-3ubuntu2.1 | [dovecot-gssapi 1:2.4.2+dfsg1-3ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-dovecot-gssapi-1-2.4.2-dfsg1-3ubuntu2.1.md) | May 12, 2026 |
| Linux | dovecot-imapd Ubuntu 25.10 (questing) | 1:2.4.1+dfsg1-5ubuntu4.2 | [dovecot-imapd 1:2.4.1+dfsg1-5ubuntu4.2](https://patchblox.com/security/data/fix/linux/ubuntu-questing-dovecot-imapd-1-2.4.1-dfsg1-5ubuntu4.2.md) | May 12, 2026 |
| Linux | dovecot-imapd Ubuntu 26.04.1 LTS (resolute) | 1:2.4.2+dfsg1-3ubuntu2.1 | [dovecot-imapd 1:2.4.2+dfsg1-3ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-dovecot-imapd-1-2.4.2-dfsg1-3ubuntu2.1.md) | May 12, 2026 |
| Linux | dovecot-ldap Ubuntu 25.10 (questing) | 1:2.4.1+dfsg1-5ubuntu4.2 | [dovecot-ldap 1:2.4.1+dfsg1-5ubuntu4.2](https://patchblox.com/security/data/fix/linux/ubuntu-questing-dovecot-ldap-1-2.4.1-dfsg1-5ubuntu4.2.md) | May 12, 2026 |
| Linux | dovecot-ldap Ubuntu 26.04.1 LTS (resolute) | 1:2.4.2+dfsg1-3ubuntu2.1 | [dovecot-ldap 1:2.4.2+dfsg1-3ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-dovecot-ldap-1-2.4.2-dfsg1-3ubuntu2.1.md) | May 12, 2026 |
| Linux | dovecot-lmtpd Ubuntu 25.10 (questing) | 1:2.4.1+dfsg1-5ubuntu4.2 | [dovecot-lmtpd 1:2.4.1+dfsg1-5ubuntu4.2](https://patchblox.com/security/data/fix/linux/ubuntu-questing-dovecot-lmtpd-1-2.4.1-dfsg1-5ubuntu4.2.md) | May 12, 2026 |
| Linux | dovecot-lmtpd Ubuntu 26.04.1 LTS (resolute) | 1:2.4.2+dfsg1-3ubuntu2.1 | [dovecot-lmtpd 1:2.4.2+dfsg1-3ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-dovecot-lmtpd-1-2.4.2-dfsg1-3ubuntu2.1.md) | May 12, 2026 |
| Linux | dovecot-managesieved Ubuntu 25.10 (questing) | 1:2.4.1+dfsg1-5ubuntu4.2 | [dovecot-managesieved 1:2.4.1+dfsg1-5ubuntu4.2](https://patchblox.com/security/data/fix/linux/ubuntu-questing-dovecot-managesieved-1-2.4.1-dfsg1-5ubuntu4.2.md) | May 12, 2026 |
| Linux | dovecot-managesieved Ubuntu 26.04.1 LTS (resolute) | 1:2.4.2+dfsg1-3ubuntu2.1 | [dovecot-managesieved 1:2.4.2+dfsg1-3ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-dovecot-managesieved-1-2.4.2-dfsg1-3ubuntu2.1.md) | May 12, 2026 |
| Linux | dovecot-mysql Ubuntu 25.10 (questing) | 1:2.4.1+dfsg1-5ubuntu4.2 | [dovecot-mysql 1:2.4.1+dfsg1-5ubuntu4.2](https://patchblox.com/security/data/fix/linux/ubuntu-questing-dovecot-mysql-1-2.4.1-dfsg1-5ubuntu4.2.md) | May 12, 2026 |
| Linux | dovecot-mysql Ubuntu 26.04.1 LTS (resolute) | 1:2.4.2+dfsg1-3ubuntu2.1 | [dovecot-mysql 1:2.4.2+dfsg1-3ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-dovecot-mysql-1-2.4.2-dfsg1-3ubuntu2.1.md) | May 12, 2026 |
| Linux | dovecot-pgsql Ubuntu 25.10 (questing) | 1:2.4.1+dfsg1-5ubuntu4.2 | [dovecot-pgsql 1:2.4.1+dfsg1-5ubuntu4.2](https://patchblox.com/security/data/fix/linux/ubuntu-questing-dovecot-pgsql-1-2.4.1-dfsg1-5ubuntu4.2.md) | May 12, 2026 |
| Linux | dovecot-pgsql Ubuntu 26.04.1 LTS (resolute) | 1:2.4.2+dfsg1-3ubuntu2.1 | [dovecot-pgsql 1:2.4.2+dfsg1-3ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-dovecot-pgsql-1-2.4.2-dfsg1-3ubuntu2.1.md) | May 12, 2026 |
| Linux | dovecot-pop3d Ubuntu 25.10 (questing) | 1:2.4.1+dfsg1-5ubuntu4.2 | [dovecot-pop3d 1:2.4.1+dfsg1-5ubuntu4.2](https://patchblox.com/security/data/fix/linux/ubuntu-questing-dovecot-pop3d-1-2.4.1-dfsg1-5ubuntu4.2.md) | May 12, 2026 |
| Linux | dovecot-pop3d Ubuntu 26.04.1 LTS (resolute) | 1:2.4.2+dfsg1-3ubuntu2.1 | [dovecot-pop3d 1:2.4.2+dfsg1-3ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-dovecot-pop3d-1-2.4.2-dfsg1-3ubuntu2.1.md) | May 12, 2026 |
| Linux | dovecot-sieve Ubuntu 25.10 (questing) | 1:2.4.1+dfsg1-5ubuntu4.2 | [dovecot-sieve 1:2.4.1+dfsg1-5ubuntu4.2](https://patchblox.com/security/data/fix/linux/ubuntu-questing-dovecot-sieve-1-2.4.1-dfsg1-5ubuntu4.2.md) | May 12, 2026 |
| Linux | dovecot-sieve Ubuntu 26.04.1 LTS (resolute) | 1:2.4.2+dfsg1-3ubuntu2.1 | [dovecot-sieve 1:2.4.2+dfsg1-3ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-dovecot-sieve-1-2.4.2-dfsg1-3ubuntu2.1.md) | May 12, 2026 |
| Linux | dovecot-solr Ubuntu 25.10 (questing) | 1:2.4.1+dfsg1-5ubuntu4.2 | [dovecot-solr 1:2.4.1+dfsg1-5ubuntu4.2](https://patchblox.com/security/data/fix/linux/ubuntu-questing-dovecot-solr-1-2.4.1-dfsg1-5ubuntu4.2.md) | May 12, 2026 |
| Linux | dovecot-solr Ubuntu 26.04.1 LTS (resolute) | 1:2.4.2+dfsg1-3ubuntu2.1 | [dovecot-solr 1:2.4.2+dfsg1-3ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-dovecot-solr-1-2.4.2-dfsg1-3ubuntu2.1.md) | May 12, 2026 |
| Linux | dovecot-sqlite Ubuntu 25.10 (questing) | 1:2.4.1+dfsg1-5ubuntu4.2 | [dovecot-sqlite 1:2.4.1+dfsg1-5ubuntu4.2](https://patchblox.com/security/data/fix/linux/ubuntu-questing-dovecot-sqlite-1-2.4.1-dfsg1-5ubuntu4.2.md) | May 12, 2026 |
| Linux | dovecot-sqlite Ubuntu 26.04.1 LTS (resolute) | 1:2.4.2+dfsg1-3ubuntu2.1 | [dovecot-sqlite 1:2.4.2+dfsg1-3ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-dovecot-sqlite-1-2.4.2-dfsg1-3ubuntu2.1.md) | May 12, 2026 |
| Linux | dovecot-submissiond Ubuntu 25.10 (questing) | 1:2.4.1+dfsg1-5ubuntu4.2 | [dovecot-submissiond 1:2.4.1+dfsg1-5ubuntu4.2](https://patchblox.com/security/data/fix/linux/ubuntu-questing-dovecot-submissiond-1-2.4.1-dfsg1-5ubuntu4.2.md) | May 12, 2026 |
| Linux | dovecot-submissiond Ubuntu 26.04.1 LTS (resolute) | 1:2.4.2+dfsg1-3ubuntu2.1 | [dovecot-submissiond 1:2.4.2+dfsg1-3ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-dovecot-submissiond-1-2.4.2-dfsg1-3ubuntu2.1.md) | May 12, 2026 |
| Linux | dovecot24 opensuse-leap 16.0 | 2.4.4-160000.1.1 | [OPENSUSE-SU-2026:21109-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-21109-1.md) | Jun 19, 2026 |
| Linux | dovecot24 sles 16.0 | 2.4.4-160000.1.1 | [SUSE-SU-2026:22185-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-22185-1.md) | Jun 19, 2026 |

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Data as of 2026-11-09T13:31:49Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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