CVE-2026-47081Network attack vector

Mailbox existence disclosure via unauthorized push registration

Published Jul 16, 2026 · Updated Jul 16, 2026

Incorrect authorization in Cyrus IMAP 3.12.2 and earlier allows remote authenticated users to detect other users' mailboxes. The XAPPLEPUSHSERVICE handler accepts an arbitrary mailbox name without enforcing the target mailbox's lookup permission, then binds change notifications to the caller's APNS device token. Any authenticated IMAP account can learn only whether a named mailbox exists and receive a notice when its modification sequence changes; message content is not exposed.

CVSS severity3.1
Low
EPSS probability0.24%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Incorrect authorization in Cyrus IMAP 3.12.2 and earlier allows remote authenticated users to detect other users' mailboxes. The XAPPLEPUSHSERVICE handler accepts an arbitrary mailbox name without enforcing the target mailbox's lookup permission, then binds change notifications to the caller's APNS device token. Any authenticated IMAP account can learn only whether a named mailbox exists and receive a notice when its modification sequence changes; message content is not exposed.

The record

CVE
CVE-2026-47081
Published
Jul 16, 2026
Updated
Jul 16, 2026
Vendor
Project Cyrus
Product
Cyrus IMAP
Classifications
CWE-863
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 16, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 16, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <3.12.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Project Cyrus · Cyrus IMAPversion=0 <3.12.3

Published CVSS scores

3.1MITRECVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-863Incorrect Authorization

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo