# CVE-2026-61907: Missing authorization in Cyrus IMAP

> An authenticated user can bypass ACLs to insert mail into other users' inboxes via JMAP snooze functionality in Cyrus IMAP.

- **Severity:** Medium 4.3 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 9 Sep 2026
- **Updated:** 14 Sep 2026
- **Also known as:** DEBIAN-CVE-2026-61907, GHSA-245j-3rxm-cqmg, UBUNTU-CVE-2026-61907

## What is CVE-2026-61907?

CVE-2026-61907 is a medium-severity missing authorization vulnerability in cyrusimap Cyrus IMAP, published on 9 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

An issue was discovered in Cyrus IMAP before 3.12.4. JMAP snooze bypasses the destination-mailbox ACL. An authenticated user with insert permissions on another user's snoozed mailbox could cause insertion of mail to that user's inbox, or any other of their mailboxes whose id was known to the user, despite having no insert permissions to the target mailbox.

Weakness: CWE-863 (Incorrect Authorization)

## Which versions are affected by CVE-2026-61907?


## How do I fix CVE-2026-61907?

Upgrade to a fixed version.

## Is CVE-2026-61907 being exploited?

There is no known exploitation of CVE-2026-61907 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-61907 and fix it if it is affected.

What it is: CVE-2026-61907 is a medium-severity missing authorization vulnerability in cyrusimap Cyrus IMAP, published on 9 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-61907 in the wild and no public exploit code.

Affected product: cyrusimap Cyrus IMAP. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-61907/ (Markdown: https://insights.sbomify.com/CVE-2026-61907/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-61907
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-61907
- OSV: https://osv.dev/vulnerability/CVE-2026-61907

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-61907/
Summaries are generated and may contain mistakes; the official description above is the record.