Quick answers
- Is CVE-2026-55888 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-55888 being exploited in the wild.
- How severe is CVE-2026-55888?
- Informational severity, published 23 October 2026.
- Which products and versions are affected?
- Flatpak Xdg-Desktop-Portal 1.22.0 and earlier.
- Is there a fix for CVE-2026-55888?
- Yes: fixed in 1.22.1. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-55888 attacked?
- It is attacked with local access, in a hosted service.
- Am I affected by CVE-2026-55888?
- Check whether you run Flatpak Xdg-Desktop-Portal at an affected version. 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.
How to fix
- Fixed in: 1.22.1
Technical details
The FileChooser.SaveFiles method accepts optional filenames that are appended to a user-selected directory by backends without proper validation. The frontend does not validate these filenames, and common backends fail to verify that files do not already exist or that paths do not contain traversal sequences. A sandboxed application can exploit this to write outside its intended sandbox boundaries.
Affected products
- Flatpak XDG Desktop Portal 1.22.0 and earlier
Timeline
- 2026-06-17: disclosed
- 2026-10-23: advisory