CVE-2021-33582

HIGH
Published Sep 1, 20214y ago · Modified Jun 17, 20262w ago
7.5 CVSS 3.1
High
Find Similar
Published Sep 1, 2021 4y ago
Last Modified Jun 17, 2026 2w ago

Description

Cyrus IMAP before 3.4.2 allows remote attackers to cause a denial of service (multiple-minute daemon hang) via input that is mishandled during hash-table interaction. Because there are many insertions into a single bucket, strcmp becomes slow. This is fixed in 3.4.2, 3.2.8, and 3.0.16.

CVSS Details

Base Score
7.5
Exploitability
3.9
Impact
3.6
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High

Threat Intelligence

No active exploitation signals — not in CISA KEV and no EPSS score yet.

Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-407

Affected Products 6

VendorProductVersionRange
cyrusimap* <3.0.16
cyrusimap*≥3.2.0  –  <3.2.8
cyrusimap*≥3.4.0  –  <3.4.2
fedoraprojectfedora34any
fedoraprojectfedora35any
debiandebian_linux9.0any

References 7

  • cyrus.topicbox.com https://cyrus.topicbox.com/groups/announce/T3dde0a2352462975-M1386fc44adf967e072f8df13/cyrus-imap-3-4-2-3-2-8-and-3-0-16-released
    PatchVendor Advisory
  • github.com https://github.com/cyrusimap/cyrus-imapd/commits/master
    PatchThird Party Advisory
  • github.com https://github.com/cyrusimap/cyrus-imapd/security/advisories
    Not ApplicableThird Party Advisory
  • lists.debian.org https://lists.debian.org/debian-lts-announce/2022/06/msg00013.html
    Mailing ListThird Party Advisory
  • lists.fedoraproject.org https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6HEO3RURJW6NLIXS7NK5PVU6MGHC4SCM/
  • lists.fedoraproject.org https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WJZB45QBUN7CZFGOWCZYUYACNBTX7LVS/
  • cyrusimap.org https://www.cyrusimap.org/imap/download/release-notes/index.html
    PatchRelease NotesVendor Advisory

Remediation

  • cyrus.topicbox.com https://cyrus.topicbox.com/groups/announce/T3dde0a2352462975-M1386fc44adf967e072f8df13/cyrus-imap-3-4-2-3-2-8-and-3-0-16-released
    PatchVendor Advisory
  • github.com https://github.com/cyrusimap/cyrus-imapd/commits/master
    PatchThird Party Advisory
  • cyrusimap.org https://www.cyrusimap.org/imap/download/release-notes/index.html
    PatchRelease NotesVendor Advisory