Prior to 1.16.4, the Flatpak portal accepts paths in the sandbox-expose options which can be app-controlled symlinks pointing at arbitrary paths. (CVE-2026-34078)
Flatpak is a Linux application sandboxing and distribution framework. Prior to 1.16.4, the Flatpak portal accepts paths in the sandbox-expose options which can be app-controlled symlinks pointing at arbitrary paths. Flatpak run mounts the resolved host path in the sandbox. This gives apps access to all host files and can be used as a primitive to gain code execution in the host context. This vulnerability is fixed in 1.16.4.
AI Analysis
Technical Summary
Flatpak versions included in Red Hat Enterprise Linux 8 and related distributions contain two vulnerabilities: CVE-2026-34078 enables arbitrary code execution through crafted symlinks in sandbox-expose options, and CVE-2026-34079 allows arbitrary file deletion on the host system due to improper validation of cache file paths. Red Hat Product Security has released an update (flatpak-1.12.9-4.el8_10) that fixes these issues. The advisory RHSA-2026:21756 details the update and affected packages across multiple architectures. No CVSS score is provided in the advisory, but the severity is rated as Important by Red Hat.
Potential Impact
Successful exploitation of CVE-2026-34078 could allow an attacker to execute arbitrary code within the Flatpak sandbox environment, potentially leading to elevated privileges or system compromise. CVE-2026-34079 could enable an attacker to delete arbitrary files on the host system, potentially disrupting system operations or causing data loss. Both vulnerabilities pose significant risks to affected systems running Flatpak on Red Hat Enterprise Linux 8.
Mitigation Recommendations
Red Hat has released an official security update for Flatpak (version 1.12.9-4.el8_10) that addresses these vulnerabilities. Users of Red Hat Enterprise Linux 8 and related distributions should apply this update promptly following Red Hat's guidance at https://access.redhat.com/articles/11258. No additional mitigation steps are indicated beyond applying the official patch.
Prior to 1.16.4, the Flatpak portal accepts paths in the sandbox-expose options which can be app-controlled symlinks pointing at arbitrary paths. (CVE-2026-34078)
Description
Flatpak is a Linux application sandboxing and distribution framework. Prior to 1.16.4, the Flatpak portal accepts paths in the sandbox-expose options which can be app-controlled symlinks pointing at arbitrary paths. Flatpak run mounts the resolved host path in the sandbox. This gives apps access to all host files and can be used as a primitive to gain code execution in the host context. This vulnerability is fixed in 1.16.4.
CVSS v3.1
Score 10.0critical
Affected software
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Flatpak versions included in Red Hat Enterprise Linux 8 and related distributions contain two vulnerabilities: CVE-2026-34078 enables arbitrary code execution through crafted symlinks in sandbox-expose options, and CVE-2026-34079 allows arbitrary file deletion on the host system due to improper validation of cache file paths. Red Hat Product Security has released an update (flatpak-1.12.9-4.el8_10) that fixes these issues. The advisory RHSA-2026:21756 details the update and affected packages across multiple architectures. No CVSS score is provided in the advisory, but the severity is rated as Important by Red Hat.
Potential Impact
Successful exploitation of CVE-2026-34078 could allow an attacker to execute arbitrary code within the Flatpak sandbox environment, potentially leading to elevated privileges or system compromise. CVE-2026-34079 could enable an attacker to delete arbitrary files on the host system, potentially disrupting system operations or causing data loss. Both vulnerabilities pose significant risks to affected systems running Flatpak on Red Hat Enterprise Linux 8.
Mitigation Recommendations
Red Hat has released an official security update for Flatpak (version 1.12.9-4.el8_10) that addresses these vulnerabilities. Users of Red Hat Enterprise Linux 8 and related distributions should apply this update promptly following Red Hat's guidance at https://access.redhat.com/articles/11258. No additional mitigation steps are indicated beyond applying the official patch.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:21756
- Cve Count
- 2
- Additional Cves
- ["CVE-2026-34079"]
Threat ID: 6a18be67e29bf47b503869fd
Added to database: 05/28/2026, 22:15:03 UTC
Last enriched: 07/07/2026, 00:51:27 UTC
Last updated: 09/14/2026, 22:01:33 UTC
Views: 153
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