{"id":"CVE-2026-76925","aliases":["EUVD-2026-71774","GHSA-639f-3fwc-hmpx","UBUNTU-CVE-2026-76925"],"status":"published","title":"Flatpak: flatpak: toctou race condition allows symlink redirection","description":"A flaw was found in Flatpak. A Time-of-check to time-of-use (TOCTOU) race condition exists in the `org.freedesktop.Flatpak.SystemHelper` component. This vulnerability occurs because a privileged `chmod` operation executes before the OSTree repository validation within the `Deploy()` function. An attacker can exploit this timing window to redirect symlinks to arbitrary files, potentially leading to unauthorized file manipulation or information disclosure.","severity":{"version":"3.1","score":5.8,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:L","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00103,"percentile":0.00953,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-367"],"published":"2026-09-04T21:02:00Z","modified":"2026-11-06T00:44:51Z","affected":[{"source":"osv","ecosystem":"Ubuntu:Pro:18.04:LTS","package":"flatpak","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.8.7-5","0.10.0-1","0.10.0-2","0.10.1-1","0.10.2-1","0.10.2.1-1","0.10.2.1-2","0.10.3-1","0.11.1-0ubuntu1","0.11.3-2","0.11.3-3","0.11.7-0ubuntu0.1","1.0.1-0ubuntu0.1","1.0.6-0ubuntu0.1","1.0.7-0ubuntu0.18.04.1","1.0.8-0ubuntu0.18.04.1","1.0.9-0ubuntu0.1","1.0.9-0ubuntu0.2","1.0.9-0ubuntu0.3","1.0.9-0ubuntu0.4","1.0.9-0ubuntu0.4+esm1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:20.04:LTS","package":"flatpak","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.4.3-1","1.6.0-1","1.6.1-1","1.6.2-1","1.6.3-1","1.6.5-0ubuntu0.1","1.6.5-0ubuntu0.2","1.6.5-0ubuntu0.3","1.6.5-0ubuntu0.4","1.6.5-0ubuntu0.5","1.6.5-0ubuntu0.5+esm1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:22.04:LTS","package":"flatpak","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.10.2-3","1.12.2-1","1.12.2-2","1.12.3-1","1.12.4-1","1.12.5-1","1.12.6-1","1.12.7-1","1.12.7-1ubuntu0.1","1.12.7-1ubuntu0.1+esm1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:24.04:LTS","package":"flatpak","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.14.4-2","1.14.5-1","1.14.5-1build1","1.14.5-1build4","1.14.5-1build5","1.14.5-1build6","1.14.6-1","1.14.6-1ubuntu0.1","1.14.6-1ubuntu0.1+esm1"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"flatpak","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.16.6-1","1.18.0-1","1.18.1-1","1.18.2-1","1.18.4-1"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"flatpak","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.16.1-2ubuntu1","1.16.1-3ubuntu1","1.16.2-1","1.16.3-1","1.16.3-1build1","1.16.4-1","1.16.4-2","1.16.6-1"]}],"products":[{"vendor":"red hat","product":"red hat enterprise linux 10"},{"vendor":"red hat","product":"red hat enterprise linux 7"},{"vendor":"red hat","product":"red hat enterprise linux 8"},{"vendor":"red hat","product":"red hat enterprise linux 9"}],"references":[{"url":"https://access.redhat.com/security/cve/CVE-2026-76925","tags":["vdb-entry","x_refsource_REDHAT"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2520099","tags":["issue-tracking","x_refsource_REDHAT"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-76925"},{"url":"https://github.com/advisories/GHSA-639f-3fwc-hmpx"},{"url":"https://ubuntu.com/security/CVE-2026-76925","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-76925","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2026-76925","title":"Flatpak: flatpak: toctou race condition allows symlink redirection","description":"A flaw was found in Flatpak. A Time-of-check to time-of-use (TOCTOU) race condition exists in the `org.freedesktop.Flatpak.SystemHelper` component. This vulnerability occurs because a privileged `chmod` operation executes before the OSTree repository validation within the `Deploy()` function. An attacker can exploit this timing window to redirect symlinks to arbitrary files, potentially leading to unauthorized file manipulation or information disclosure.","status":"published","published":"2026-09-04T21:02:00.079Z","modified":"2026-11-06T00:44:51.07Z","cvss":[{"version":"3.1","score":5.8,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:L","level":"medium","assessor":"cna"}],"cwes":["CWE-367"],"updated_at":"2026-11-06T01:55:46.939755Z"}],"euvd":[{"id":"EUVD-2026-71774","description":"A flaw was found in Flatpak. A Time-of-check to time-of-use (TOCTOU) race condition exists in the `org.freedesktop.Flatpak.SystemHelper` component. This vulnerability occurs because a privileged `chmod` operation executes before the OSTree repository validation within the `Deploy()` function. An attacker can exploit this timing window to redirect symlinks to arbitrary files, potentially leading to unauthorized file manipulation or information disclosure.","status":"published","published":"2026-09-04T21:02:00Z","modified":"2026-11-06T00:44:51Z","cvss":[{"version":"3.1","score":5.8,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:L","level":"medium"}],"updated_at":"2026-11-06T02:02:53.341523Z"}],"ghsa":[{"id":"GHSA-639f-3fwc-hmpx","title":"A flaw was found in Flatpak. A Time-of-check to time-of-use (TOCTOU) race condition exists in the...","description":"A flaw was found in Flatpak. A Time-of-check to time-of-use (TOCTOU) race condition exists in the `org.freedesktop.Flatpak.SystemHelper` component. This vulnerability occurs because a privileged `chmod` operation executes before the OSTree repository validation within the `Deploy()` function. An attacker can exploit this timing window to redirect symlinks to arbitrary files, potentially leading to unauthorized file manipulation or information disclosure.","status":"published","published":"2026-09-05T00:31:06Z","modified":"2026-09-05T00:31:10Z","cvss":[{"version":"3.1","score":5.8,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:L","level":"medium"}],"cwes":["CWE-367"],"updated_at":"2026-11-02T15:11:24.326884Z"}],"nvd":[{"id":"CVE-2026-76925","description":"A flaw was found in Flatpak. A Time-of-check to time-of-use (TOCTOU) race condition exists in the `org.freedesktop.Flatpak.SystemHelper` component. This vulnerability occurs because a privileged `chmod` operation executes before the OSTree repository validation within the `Deploy()` function. An attacker can exploit this timing window to redirect symlinks to arbitrary files, potentially leading to unauthorized file manipulation or information disclosure.","status":"published","published":"2026-09-04T22:17:18.19Z","modified":"2026-11-06T01:17:51.477Z","cvss":[{"version":"3.1","score":5.8,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:L","level":"medium","assessor":"secondary"}],"cwes":["CWE-367"],"updated_at":"2026-11-06T06:59:05.303911Z"}],"osv":[{"id":"UBUNTU-CVE-2026-76925","description":"A flaw was found in Flatpak. A Time-of-check to time-of-use (TOCTOU) race condition exists in the `org.freedesktop.Flatpak.SystemHelper` component. This vulnerability occurs because a privileged `chmod` operation executes before the OSTree repository validation within the `Deploy()` function. An attacker can exploit this timing window to redirect symlinks to arbitrary files, potentially leading to unauthorized file manipulation or information disclosure.","status":"published","published":"2026-09-04T22:17:00Z","modified":"2026-10-17T13:01:07.396956515Z","cvss":[{"version":"3.1","score":5.8,"vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:L/A:L","level":"medium"}],"updated_at":"2026-11-02T16:57:13.483205Z"}]}}