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Fencer Vulns
high 8.3

CVE-2026-55889 json

XDG Desktop Portal: Drag-and-drop and copy-paste theft via predictable FileTransfer key

published 2026-10-23 16 d ago modified 2026-10-23 16 d ago also EUVD-2026-108751

cvss
8.3
version 4.0, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 28%
public exploits
0
none known

Summary

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.

Patch / fix

  • xdg-desktop-portal Debian 14 1.22.1+ds-1

debian advisories DEBIAN-CVE-2026-55889

  • xdg-desktop-portal SLES for SAP 15 SP5, SLES 15 SP5-LTSS, SLE High Performance Computing 15 SP5-LTSS +1 more 1.16.0-150500.3.13.1

suse advisories SUSE-SU-2026:5098-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-55889 updated cvss 5.3

xdg-desktop-portal: xdg-desktop-portal: unauthorized data disclosure via predictable token generation

  • Red Hat Enterprise Linux 7 xdg-desktop-portal, xdg-desktop-portal 1.20.0-2.el10 Red Hat Enterprise Linux 8 xdg-desktop-portal, xdg-desktop-portal 1.20.0-2.el10 Red Hat Enterprise Linux 9 xdg-desktop-portal 1.20.0-2.el10 Red Hat Enterprise Linux 10 xdg-desktop-portal 1.20.0-2.el10
    affected: workaround, no fix available “Fix deferred”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
16 d ago

Exploit prediction

0.34% chance of exploitation in the next 30 days, higher than 28% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 4.0 8.3 CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N
CNA 4.0 8.3 CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected products

  • flatpak xdg-desktop-portal

Classification

Weakness
  • CWE-330 Use of Insufficiently Random Values
  • CWE-337 Predictable Seed in Pseudo-Random Number Generator (PRNG)

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.