CVE-2019-10063

Severity: critical (CVSS 9.0 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2019-03-26 · updated 2026-06-17
Weakness: CWE-20

Description

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.

Affected products

flatpak: before 1.0.8; from 1.1.0 through 1.1.3; from 1.2.0 before 1.2.4; 1.3.0 — fixed in 1.0.8, 1.2.4

How to fix

Upgrade to a fixed version: flatpak 1.0.8, 1.2.4. Check the vendor advisory for mitigations.

References

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