Flatpak: flatpak: sandboxed app can signal unsandboxed processes in the same process group (CVE-2026-97029) | HOL Guard CVE

Medium · CVSS 5.7CVE-2026-97029

Flatpak: flatpak: sandboxed app can signal unsandboxed processes in the same process group

Answer in brief

CVE-2026-97029 records a Medium severity (CVSS 5.7) vulnerability in Flatpak: flatpak: sandboxed app can signal unsandboxed processes in the same process group. The current sources do not mark it as known exploited. The current feed maps Red Hat/flatpak (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 29, 2026Updated Sep 29, 2026Source checked Sep 29, 2026First seen by HOL Sep 29, 2026Material review Sep 29, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 5.7
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Not reported

Why this deserves its current priority

CVSS is 5.7. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Red Hat/flatpak (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Red Hat/flatpakgeneric	*	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Red Hat/flatpak.
Review the reported fix. Source-reported workaround: Run Flatpak apps in a new session (setsid flatpak run ... or setsid() in the parent) or a new process group (setpgid (0, 0) in the parent), or avoid running untrusted Flatpak apps.

Evidence timeline and material changes

Published upstream
Sep 29, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 29, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 29, 2026

Sources and claim methodology

Upstream source description

Flatpak's process ID namespace separation does not prevent a sandboxed app's kill(0, signal) or killpg(0, signal) calls from reaching processes outside the sandbox that share the same process group. A malicious or compromised Flatpak app can use this to cause denial of service by terminating processes outside its sandbox, such as the desktop shell.

Quoted source text, attributed separately from HOL analysis.