High severity · published Oct 23, 2026
CVE-2026-55889
XDG Desktop Portal: Drag-and-drop and copy-paste theft via predictable FileTransfer key
New
8.3
CVSS
0.3%
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 FileTransfer.RetrieveFiles method to redirect drag-and-drop and copy-paste data targeted at other applications to itself. Some portals generate tokens which provide access to resources. The sharing of the token transfers access to the resource and is supposed to happen out of band. The tokens were generated with g_random_int or g_uuid_string_random, both of which use GLib's GRand based on the Mersenne Twister PRNG which created a stream of reproducible random numbers. By generating enough tokens, the state of the GRand can be recover and with it, the next tokens can be predictedinsufin. This issue has been patched in version 1.22.1.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 28% 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
Affected product
XD
xdg-desktop-portal
flatpak
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