# CVE-2026-10631: Zimbra Collaboration Suite EWS Extension Authorization Bypass via Crafted Composite Folder/Item Identifier

> Authenticated users can read arbitrary mailbox items and attachments from other accounts via the EWS FindItem handler.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/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:** No
- **Published:** 8 Oct 2026
- **Updated:** 8 Oct 2026
- **Also known as:** GHSA-7jfc-2g3q-h5mf

## What is CVE-2026-10631?

CVE-2026-10631 is a medium-severity missing authorization vulnerability in Zimbra Collaboration Suite, published on 8 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

An authorization bypass in the EWS FindItem handler of Zimbra Collaboration Suite 10.1.0 through 10.1.19 allows an authenticated user with EWS enabled to read complete mailbox items, including raw MIME and attachments, from arbitrary local accounts without a share or delegation grant.

Weakness: CWE-639 (Authorization Bypass Through User-Controlled Key)

## Which versions are affected by CVE-2026-10631?


## How do I fix CVE-2026-10631?

No fix has been published for CVE-2026-10631 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-10631 being exploited?

There is no known exploitation of CVE-2026-10631 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-10631 and fix it if it is affected.

What it is: CVE-2026-10631 is a medium-severity missing authorization vulnerability in Zimbra Collaboration Suite, published on 8 Oct 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-2026-10631 in the wild and no public exploit code.

Affected product: Zimbra Collaboration Suite. 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-2026-10631/ (Markdown: https://insights.sbomify.com/CVE-2026-10631/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-10631
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-10631
- OSV: https://osv.dev/vulnerability/CVE-2026-10631

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-10631/
Summaries are generated and may contain mistakes; the official description above is the record.