# CVE-2021-33582: cyrus-imapd: The Cyrus IMAP server provides access to personal mail, system-wide bulletin boards, news-feeds, calendar and contact...

CVE-2021-33582 is fixed in 12 products on 1 platform, first by cyrus-admin 2.5.10-3ubuntu1.1+esm1, released August 31, 2021. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2021-33582
- Priority: High
- CVSS: 7.5 (Important)
- EPSS: 0.0310
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Aug 31, 2021

## Description

The Cyrus IMAP server provides access to personal mail, system-wide bulletin boards, news-feeds, calendar and contacts through the IMAP, JMAP, NNTP, CalDAV and CardDAV protocols.  Security Fix(es):  * cyrus-imapd: Denial of service via string hashing algorithm collisions (CVE-2021-33582)  For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | cyrus-admin Ubuntu 18.04.6 LTS (bionic) | 2.5.10-3ubuntu1.1+esm1 | [cyrus-admin 2.5.10-3ubuntu1.1+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-cyrus-admin-2.5.10-3ubuntu1.1-esm1.md) | Aug 31, 2021 |
| Linux | cyrus-admin Ubuntu 20.04 LTS (focal) | 3.0.13-5ubuntu0.1~esm1 | [cyrus-admin 3.0.13-5ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-cyrus-admin-3.0.13-5ubuntu0.1-esm1.md) | Aug 31, 2021 |
| Linux | cyrus-caldav Ubuntu 18.04.6 LTS (bionic) | 2.5.10-3ubuntu1.1+esm1 | [cyrus-caldav 2.5.10-3ubuntu1.1+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-cyrus-caldav-2.5.10-3ubuntu1.1-esm1.md) | Aug 31, 2021 |
| Linux | cyrus-caldav Ubuntu 20.04 LTS (focal) | 3.0.13-5ubuntu0.1~esm1 | [cyrus-caldav 3.0.13-5ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-cyrus-caldav-3.0.13-5ubuntu0.1-esm1.md) | Aug 31, 2021 |
| Linux | cyrus-clients Ubuntu 18.04.6 LTS (bionic) | 2.5.10-3ubuntu1.1+esm1 | [cyrus-clients 2.5.10-3ubuntu1.1+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-cyrus-clients-2.5.10-3ubuntu1.1-esm1.md) | Aug 31, 2021 |
| Linux | cyrus-clients Ubuntu 20.04 LTS (focal) | 3.0.13-5ubuntu0.1~esm1 | [cyrus-clients 3.0.13-5ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-cyrus-clients-3.0.13-5ubuntu0.1-esm1.md) | Aug 31, 2021 |
| Linux | cyrus-common Ubuntu 18.04.6 LTS (bionic) | 2.5.10-3ubuntu1.1+esm1 | [cyrus-common 2.5.10-3ubuntu1.1+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-cyrus-common-2.5.10-3ubuntu1.1-esm1.md) | Aug 31, 2021 |
| Linux | cyrus-common Ubuntu 20.04 LTS (focal) | 3.0.13-5ubuntu0.1~esm1 | [cyrus-common 3.0.13-5ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-cyrus-common-3.0.13-5ubuntu0.1-esm1.md) | Aug 31, 2021 |
| Linux | cyrus-imapd RHEL 8 | 0:3.0.7-20.el8_4.1 | [RHSA-2021:3492](https://patchblox.com/security/data/fix/linux/rhsa-2021-3492.md) | Sep 13, 2021 |
| Linux | cyrus-imapd Ubuntu 18.04.6 LTS (bionic) | 2.5.10-3ubuntu1.1+esm1 | [cyrus-imapd 2.5.10-3ubuntu1.1+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-cyrus-imapd-2.5.10-3ubuntu1.1-esm1.md) | Aug 31, 2021 |
| Linux | cyrus-imapd Ubuntu 20.04 LTS (focal) | 3.0.13-5ubuntu0.1~esm1 | [cyrus-imapd 3.0.13-5ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-cyrus-imapd-3.0.13-5ubuntu0.1-esm1.md) | Aug 31, 2021 |
| Linux | cyrus-imapd ol 8 | 0:3.0.7-20.el8_4.1 | [ELSA-2021-3492](https://patchblox.com/security/data/fix/linux/elsa-2021-3492.md) | Sep 13, 2021 |
| Linux | cyrus-imapd-utils RHEL 8 | 0:3.0.7-20.el8_4.1 | [RHSA-2021:3492](https://patchblox.com/security/data/fix/linux/rhsa-2021-3492.md) | Sep 13, 2021 |
| Linux | cyrus-imapd-utils ol 8 | 0:3.0.7-20.el8_4.1 | [ELSA-2021-3492](https://patchblox.com/security/data/fix/linux/elsa-2021-3492.md) | Sep 13, 2021 |
| Linux | cyrus-imapd-vzic RHEL 8 | 0:3.0.7-20.el8_4.1 | [RHSA-2021:3492](https://patchblox.com/security/data/fix/linux/rhsa-2021-3492.md) | Sep 13, 2021 |
| Linux | cyrus-imapd-vzic ol 8 | 0:3.0.7-20.el8_4.1 | [ELSA-2021-3492](https://patchblox.com/security/data/fix/linux/elsa-2021-3492.md) | Sep 13, 2021 |
| Linux | cyrus-murder Ubuntu 18.04.6 LTS (bionic) | 2.5.10-3ubuntu1.1+esm1 | [cyrus-murder 2.5.10-3ubuntu1.1+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-cyrus-murder-2.5.10-3ubuntu1.1-esm1.md) | Aug 31, 2021 |
| Linux | cyrus-murder Ubuntu 20.04 LTS (focal) | 3.0.13-5ubuntu0.1~esm1 | [cyrus-murder 3.0.13-5ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-cyrus-murder-3.0.13-5ubuntu0.1-esm1.md) | Aug 31, 2021 |
| Linux | cyrus-nntpd Ubuntu 18.04.6 LTS (bionic) | 2.5.10-3ubuntu1.1+esm1 | [cyrus-nntpd 2.5.10-3ubuntu1.1+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-cyrus-nntpd-2.5.10-3ubuntu1.1-esm1.md) | Aug 31, 2021 |
| Linux | cyrus-nntpd Ubuntu 20.04 LTS (focal) | 3.0.13-5ubuntu0.1~esm1 | [cyrus-nntpd 3.0.13-5ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-cyrus-nntpd-3.0.13-5ubuntu0.1-esm1.md) | Aug 31, 2021 |
| Linux | cyrus-pop3d Ubuntu 18.04.6 LTS (bionic) | 2.5.10-3ubuntu1.1+esm1 | [cyrus-pop3d 2.5.10-3ubuntu1.1+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-cyrus-pop3d-2.5.10-3ubuntu1.1-esm1.md) | Aug 31, 2021 |
| Linux | cyrus-pop3d Ubuntu 20.04 LTS (focal) | 3.0.13-5ubuntu0.1~esm1 | [cyrus-pop3d 3.0.13-5ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-cyrus-pop3d-3.0.13-5ubuntu0.1-esm1.md) | Aug 31, 2021 |
| Linux | cyrus-replication Ubuntu 18.04.6 LTS (bionic) | 2.5.10-3ubuntu1.1+esm1 | [cyrus-replication 2.5.10-3ubuntu1.1+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-cyrus-replication-2.5.10-3ubuntu1.1-esm1.md) | Aug 31, 2021 |
| Linux | cyrus-replication Ubuntu 20.04 LTS (focal) | 3.0.13-5ubuntu0.1~esm1 | [cyrus-replication 3.0.13-5ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-cyrus-replication-3.0.13-5ubuntu0.1-esm1.md) | Aug 31, 2021 |
| Linux | libcyrus-imap-perl Ubuntu 18.04.6 LTS (bionic) | 2.5.10-3ubuntu1.1+esm1 | [libcyrus-imap-perl 2.5.10-3ubuntu1.1+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-libcyrus-imap-perl-2.5.10-3ubuntu1.1-esm1.md) | Aug 31, 2021 |
| Linux | libcyrus-imap-perl Ubuntu 20.04 LTS (focal) | 3.0.13-5ubuntu0.1~esm1 | [libcyrus-imap-perl 3.0.13-5ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-libcyrus-imap-perl-3.0.13-5ubuntu0.1-esm1.md) | Aug 31, 2021 |

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