CVE-2026-61908
Cyrus IMAP Out-of-Bounds Read Vulnerability
Description
An issue was discovered in Cyrus IMAP before 3.12.4. A JMAP email-header blob ID can reference an out-of-bounds index. An authenticated user could attempt to download a crafted JMAP blob ID of the form H<emailid>-<index>, which could read past the end of the internal blob_headers array during download, exposing adjacent heap memory.
INFO
Published Date :
Sept. 9, 2026, 8:18 p.m.
Last Modified :
Sept. 16, 2026, 3:24 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] | ||||
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update Cyrus IMAP to version 3.12.4 or later.
- Apply vendor-supplied patches if available.
- Review access controls for JMAP.
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-2026-61908.
| URL | Resource |
|---|---|
| https://cyrusimap.org | Product |
| https://www.cyrusimap.org/3.12/imap/download/release-notes/3.10/x/3.10.4.html | Release Notes |
| https://www.cyrusimap.org/3.12/imap/download/release-notes/3.12/x/3.12.4.html | Release Notes |
| https://www.cyrusimap.org/3.12/imap/download/release-notes/3.8/x/3.8.8.html | Release Notes |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-61908 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-2026-61908
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-2026-61908 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-61908 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.
-
Initial Analysis by [email protected]
Sep. 16, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N Added CPE Configuration OR *cpe:2.3:a:cyrus:imap:*:*:*:*:*:*:*:* versions up to (excluding) 3.8.8 *cpe:2.3:a:cyrus:imap:*:*:*:*:*:*:*:* versions from (including) 3.11.0 up to (excluding) 3.12.4 *cpe:2.3:a:cyrus:imap:*:*:*:*:*:*:*:* versions from (including) 3.9.0 up to (excluding) 3.10.4 Added Reference Type MITRE: https://cyrusimap.org Types: Product Added Reference Type MITRE: https://www.cyrusimap.org/3.12/imap/download/release-notes/3.10/x/3.10.4.html Types: Release Notes Added Reference Type MITRE: https://www.cyrusimap.org/3.12/imap/download/release-notes/3.12/x/3.12.4.html Types: Release Notes Added Reference Type MITRE: https://www.cyrusimap.org/3.12/imap/download/release-notes/3.8/x/3.8.8.html Types: Release Notes -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Sep. 10, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-61908', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-09-10T18:58:39.917684Z'} -
New CVE Received by [email protected]
Sep. 09, 2026
Action Type Old Value New Value Added Description An issue was discovered in Cyrus IMAP before 3.12.4. A JMAP email-header blob ID can reference an out-of-bounds index. An authenticated user could attempt to download a crafted JMAP blob ID of the form H<emailid>-<index>, which could read past the end of the internal blob_headers array during download, exposing adjacent heap memory. Added CVSS V3.1 AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N Added CWE CWE-125 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/61xxx/CVE-2026-61908.json">CVE-2026-61908</a> Added Reference https://cyrusimap.org Added Reference https://www.cyrusimap.org/3.12/imap/download/release-notes/3.10/x/3.10.4.html Added Reference https://www.cyrusimap.org/3.12/imap/download/release-notes/3.12/x/3.12.4.html Added Reference https://www.cyrusimap.org/3.12/imap/download/release-notes/3.8/x/3.8.8.html