{"id":"UBUNTU-CVE-2026-55888","details":"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.","modified":"2026-10-27T04:17:56.185142129Z","published":"2026-10-26T00:00:00Z","upstream":["CVE-2026-55888"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-55888"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-55888"},{"type":"REPORT","url":"https://github.com/flatpak/xdg-desktop-portal/releases/tag/1.22.1"},{"type":"REPORT","url":"https://github.com/flatpak/xdg-desktop-portal/security/advisories/GHSA-cm83-2936-gxjm"}],"affected":[{"package":{"name":"xdg-desktop-portal","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/xdg-desktop-portal?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.0.3-0ubuntu0.0"],"ecosystem_specific":{"binaries":[{"binary_name":"xdg-desktop-portal","binary_version":"1.0.3-0ubuntu0.0"},{"binary_name":"xdg-desktop-portal-tests","binary_version":"1.0.3-0ubuntu0.0"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-55888.json"}},{"package":{"name":"xdg-desktop-portal","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/xdg-desktop-portal?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.8-2","0.8-3","0.9-1","0.9-2","0.10-0ubuntu1","0.10-2","0.10-4","0.11-1","1.0.3-0ubuntu0.2"],"ecosystem_specific":{"binaries":[{"binary_name":"xdg-desktop-portal","binary_version":"1.0.3-0ubuntu0.2"},{"binary_name":"xdg-desktop-portal-tests","binary_version":"1.0.3-0ubuntu0.2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-55888.json"}},{"package":{"name":"xdg-desktop-portal","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/xdg-desktop-portal?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.4.2-2","1.4.2-3","1.6.0-1","1.6.0-1ubuntu1","1.6.0-1ubuntu2"],"ecosystem_specific":{"binaries":[{"binary_version":"1.6.0-1ubuntu2","binary_name":"xdg-desktop-portal"},{"binary_name":"xdg-desktop-portal-tests","binary_version":"1.6.0-1ubuntu2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-55888.json"}},{"package":{"name":"xdg-desktop-portal","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/xdg-desktop-portal?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.8.1-1build1","1.10.1-2","1.10.1-4","1.12.1-1","1.12.1-1build1","1.12.1-1ubuntu1","1.14.1-1","1.14.1-2","1.14.2-1","1.14.2-1ubuntu1","1.14.2-1ubuntu2","1.14.3-0ubuntu2","1.14.3-0ubuntu2.22.04.1","1.14.4-1ubuntu1~22.04.1","1.14.4-1ubuntu2~22.04.1","1.14.4-1ubuntu2~22.04.2"],"ecosystem_specific":{"binaries":[{"binary_name":"xdg-desktop-portal","binary_version":"1.14.4-1ubuntu2~22.04.2"},{"binary_version":"1.14.4-1ubuntu2~22.04.2","binary_name":"xdg-desktop-portal-tests"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-55888.json"}},{"package":{"name":"xdg-desktop-portal","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/xdg-desktop-portal?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.18.0-1ubuntu1","1.18.2-1ubuntu1","1.18.2-1ubuntu3","1.18.2-1ubuntu4","1.18.3-1ubuntu1","1.18.4-1ubuntu2","1.18.4-1ubuntu2.24.04.1","1.18.4-1ubuntu2.24.04.2","1.18.4-1ubuntu2.24.04.3"],"ecosystem_specific":{"binaries":[{"binary_name":"xdg-desktop-portal","binary_version":"1.18.4-1ubuntu2.24.04.3"},{"binary_version":"1.18.4-1ubuntu2.24.04.3","binary_name":"xdg-desktop-portal-tests"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-55888.json"}},{"package":{"name":"xdg-desktop-portal","ecosystem":"Ubuntu:26.10","purl":"pkg:deb/ubuntu/xdg-desktop-portal?arch=source&distro=stonking"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.21.1+ds-1ubuntu3","1.21.1+ds-1ubuntu4","1.21.1+ds-1ubuntu5","1.21.1+ds-1ubuntu6"],"ecosystem_specific":{"binaries":[{"binary_name":"xdg-desktop-portal","binary_version":"1.21.1+ds-1ubuntu6"},{"binary_name":"xdg-desktop-portal-tests","binary_version":"1.21.1+ds-1ubuntu6"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-55888.json"}},{"package":{"name":"xdg-desktop-portal","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/xdg-desktop-portal?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.20.3+ds-1ubuntu1","1.20.3+ds-1ubuntu2","1.21.0+ds-1ubuntu3","1.21.0+ds-1ubuntu4","1.21.0+ds-1ubuntu6","1.21.0+ds-1ubuntu7","1.21.0+ds-1ubuntu8","1.21.1+ds-1ubuntu1","1.21.1+ds-1ubuntu2","1.21.1+ds-1ubuntu3","1.21.1+ds-1ubuntu3.1"],"ecosystem_specific":{"binaries":[{"binary_version":"1.21.1+ds-1ub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