High severity · published Oct 23, 2026
CVE-2026-55888
XDG Desktop Portal: Arbitrary file access via SaveFiles "files" option path traversal
New
8.8
CVSS
0.4%
EPSS
No
On KEV
Description
XDG Desktop Portal is a desktop integration portal. Prior to version 1.22.1, malicious sandboxed applications can use the FileChooser.SaveFiles method to gain arbitrary file access to non-existing files on the host (limited to files the user has access to). The FileChooser.SaveFiles method takes optional filenames which get appended to the selected directory by backends. The backends are supposed to check that the file does not exist yet. The filenames are not validated by the frontend and also not by common backends. This issue has been patched in version 1.22.1.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 32% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
XD
xdg-desktop-portal · flatpak
< 1.22.1 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-55888
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-55888
github.com
https://github.com/flatpak/xdg-desktop-portal/releases/tag/1.22.1
github.com
https://github.com/flatpak/xdg-desktop-portal/security/advisories/GHSA-cm83-2936-gxjm
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