SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

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.

CRITICAL 9.0EPSS 1.91%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.91%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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.

CVSS 3.0
9.0 CRITICALCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
EPSS
1.91% probability · 80th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-20
Affected
flatpak/flatpak
Source
cve@mitre.org
EPSS trend
0%3%5%27 October 2026: 1.91%27 October 202627 October 2026

EPSS 1.9% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.