# CVE-2026-110777: GNOME evolution-data-server file read via CalDAV ATTACH property

Source: https://junglewise.ai/threats/cve-2026-110777-a-flaw-was-found-in-evolution-data-server-calendar-events  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-10-14. Updated: 2026-10-16  
License: CC BY 4.0 with a link back

CVE-2026-110777 · Severity: medium · CVSS 5.7 · Published 2026-10-14

Evolution Data Server is a mail and calendar synchronization component used by GNOME applications. A flaw allows attackers who can create calendar events on a shared CalDAV server to trick users into uploading arbitrary local files (like configuration files or documents) to the server when the user interacts with a malicious event containing a file:// URI. This enables data theft from users who have access to shared calendars.

Vendors: [Gnome](https://junglewise.ai/threats/vendors/gnome).

## Quick answers

**Is CVE-2026-110777 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-110777 being exploited in the wild.

**How severe is CVE-2026-110777?** Medium severity, with a CVSS score of 5.7, published 14 October 2026.

**Which products and versions are affected?** GNOME evolution-data-server.

**Is there a fix for CVE-2026-110777?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-110777 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-110777?** Check whether you run Gnome Evolution Data Server. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability exists in evolution-data-server's handling of ATTACH properties in calendar events. When processing CalDAV events containing file:// URIs, the application automatically reads the local file, base64-encodes it, and uploads it to the server without verifying whether the attachment originated from the server or was added locally. An attacker with CalDAV write access can craft malicious events that trigger arbitrary local file reads when a user opens or saves the event.

## Affected products

- GNOME evolution-data-server

## Timeline

- 2026-10-14: disclosed

## References

- [https://gitlab.gnome.org/GNOME/evolution-data-server](https://gitlab.gnome.org/GNOME/evolution-data-server)
- [https://access.redhat.com/downloads/content/package-browser/](https://access.redhat.com/downloads/content/package-browser/)

## Related threats

- [GNOME Evolution Data Server arbitrary file deletion in addressbook backend](https://junglewise.ai/threats/cve-2026-2604-gnome-evolution-data-server-arbitrary-file-deletion-in-addressbook)