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CVE-2017-14230: Cyrus Imap: Information disclosure

CVE-2017-14230 is rated critical with a CVSS v3.0 base score of 9.1 and affects Cyrus Imap. Per its scoring, it can be exploited over the network, without authentication, without any user interaction.

Vulnerability description

In the mboxlist_do_find function in imap/mboxlist.c in Cyrus IMAP before 3.0.4, an off-by-one error in prefix calculation for the LIST command caused use of uninitialized memory, which might allow remote attackers to obtain sensitive information or cause a denial of service (daemon crash) via a 'LIST "" "Other Users"' command.

Severity breakdown

CVSS v3.0 9.1: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

• Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
• Attack complexity: Low. No special conditions; the attack can be repeated reliably.
• Privileges required: None. No account or prior access is needed.
• User interaction: None. No action from any user is needed.
• Scope: Unchanged. Impact stays within the vulnerable component.
• Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
• Integrity impact: None. No loss of integrity.
• Availability impact: High. Total loss of availability; the component can be shut down.

Underlying weakness

CWE-20: Improper Input Validation

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.

Affected products

• Cyrus Imap: up to and including 3.0.3

References

• https://github.com/cyrusimap/cyrus-imapd/commit/6bd33275368edfa71ae117de895488584678ac79
• https://github.com/cyrusimap/cyrus-imapd/issues/2132
• https://lists.andrew.cmu.edu/pipermail/cyrus-announce/2017-September/000145.html
• https://www.cyrusimap.org/imap/download/release-notes/3.0/x/3.0.4.html