CVE-2019-10063: Flatpak before 1.0.8, 1.1.x and 1.2.x before 1.2.4, and 1.3.x before 1.3.1 allows a sandbox bypass.

Flatpak before 1.0.8, 1.1.x and 1.2.x before 1.2.4, and 1.3.x before 1.3.1 allows a sandbox bypass.

Flatpak before 1.0.8, 1.1.x and 1.2.x before 1.2.4, and 1.3.x before 1.3.1 allows a sandbox bypass. Flatpak versions since 0.8.1 address CVE-2017-5226 by using a seccomp filter to prevent sandboxed apps from using the TIOCSTI ioctl, which could otherwise be used to inject commands into the controlling terminal so that they would be executed outside the sandbox after the sandboxed app exits. This fix was incomplete: on 64-bit platforms, the seccomp filter could be bypassed by an ioctl request number that has TIOCSTI in its 32 least significant bits and an arbitrary nonzero value in its 32 most significant bits, which the Linux kernel would treat as equivalent to TIOCSTI.

Description from the National Vulnerability Database, published by MITRE

What it means for a small business

If your business uses Flatpak, install the vendor's update. If you're not sure whether you use it, ask whoever manages your computers.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 1.9%, higher than 79% of CVEs. That’s above average: worth scheduling this week. Scored October 28, 2026, updated daily.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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