CVE-2026-47086
Cyrus IMAP URLAUTH Token ACL Bypass
Description
An issue was discovered in cyrus-imapd in Cyrus IMAP through 3.12.2. GENURLAUTH-issued tokens can bypass ACLs. Any authenticated user could mint a URLAUTH token (via the GENURLAUTH command) for any mailbox they could name, even without read access on it. This would allow reading mail from mailboxes despite having no granted permissions.
INFO
Published Date :
July 16, 2026, 7:16 p.m.
Last Modified :
July 16, 2026, 7:16 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | LOW | 8254265b-2729-46b6-b9e3-3dfca2d5bfca | ||||
| CVSS 3.1 | LOW | [email protected] |
Solution
- Update Cyrus IMAP to a patched version.
- Apply vendor patches for Cyrus IMAP.
- Verify access controls are enforced.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-47086.
| URL | Resource |
|---|---|
| https://www.cyrusimap.org/3.12/imap/download/release-notes/3.12/x/3.12.3.html | |
| https://www.cyrusimap.org/imap/download/release-notes/index.html |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-47086 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-47086
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-47086 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-47086 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Jul. 16, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'cyrusimap', 'product': 'Cyrus IMAP', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '3.12.3', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}] Added Description An issue was discovered in cyrus-imapd in Cyrus IMAP through 3.12.2. GENURLAUTH-issued tokens can bypass ACLs. Any authenticated user could mint a URLAUTH token (via the GENURLAUTH command) for any mailbox they could name, even without read access on it. This would allow reading mail from mailboxes despite having no granted permissions. Added CVSS V3.1 AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:N/A:N Added CWE CWE-863 Added Reference https://www.cyrusimap.org/3.12/imap/download/release-notes/3.12/x/3.12.3.html Added Reference https://www.cyrusimap.org/imap/download/release-notes/index.html -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jul. 16, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-47086', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-07-16T18:46:52.503524Z'}