Description
An issue was discovered in cyrus-imapd in Cyrus IMAP through 3.12.2. There is an XAPPLEPUSHSERVICE folder existence oracle and push hijack. An authenticated IMAP user could probe for the existence of arbitrary mailboxes on other users' accounts via the XAPPLEPUSHSERVICE command and then create Apple Push Notification Service notifications for new mail in those mailboxes to their own APNS device. This did not leak any data about the content of mailboxes. Instead, a "mailbox has changed" notice would be pushed when the mailbox modseq changed.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| cyrusimap | Cyrus IMAP | < 3.12.3 | 3.12.3 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | cyrus-imapd | 3.12.3-1 | — |
| Debian 13 | cyrus-imapd | 3.10.2-1+deb13u2 | — |
| Debian 12 | cyrus-imapd | 3.6.1-4+deb12u5 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | cyrus-imapd | No fix yet | — |
| Ubuntu 26.04 LTS | cyrus-imapd | No fix yet | — |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 24.04 LTS | cyrus-imapd | No fix yet | — |
| Ubuntu Pro 22.04 LTS | cyrus-imapd | No fix yet | — |
| Ubuntu Pro 20.04 LTS | cyrus-imapd | No fix yet | — |
| Ubuntu Pro 18.04 LTS | cyrus-imapd | No fix yet | — |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 16.0 | cyrus-imapd | 3.8.7-bp160.1.1 | openSUSE-SU-2026:21368-1 |
Advisories 2
- WID-SEC-2026-2387 cyrus imap: Mehrere Schwachstellen BSI CERT-Bund (WID) · Sep 1, 2026
- openSUSE-SU-2026:21368-1 Security update for cyrus-imapd SUSE / openSUSE Security Updates · Jul 19, 2026