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TI-2026-63871 Aliases CVE-2026-96807

In Flatpak before 1.18.1, a malicious sandboxed app can replace ~/.var/app/$appid/.ld.so…

Priority LOW 18CWE-61Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
None
Attack complexity
High
Impact type
—
Confidentiality · integrity · availability
None · Low · Low
Fix status
Partial Red Hat: 4 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.

Summary

In Flatpak before 1.18.1, a malicious sandboxed app can replace ~/.var/app/$appid/.ld.so with a symlink, causing regenerate_ld_cache to write files at an arbitrary location. The filenames and content are not attacker controlled, making this hard to exploit.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00118 1st percentileScored 2026-11-07
Fix Partial Flatpak (Flatpak): 1.18.1Red Hat: 4 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
flatpakFlatpakbefore 1.18.11.18.1Patch availableCNA
  • Flatpak Vendorflatpak Affected before 1.18.1 Fixed in 1.18.1 Patch available CNA

Remediation

  • Fix · CNA Flatpak (Flatpak) Fixed in 1.18.1

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    Flatpak 1.18.1

    2 records Highest priority Priority LOW 2 LOW

    Other records, highest priority first

    • TI-2026-63872 In Flatpak before 1.18.1, the revokefs writer, used by the flatpak-system-helper to…Priority LOW 33
    Show all 2 records →

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 7AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 8AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-96807

References

Other 1

  • TI-2026-28833 flatpak-builder has a path traversal leading to arbitrary file read on host when installing licence files CVSS 4.0HIGH 7.1
  • TI-2026-26401 Flatpak has a complete sandbox escape leading to host file access and code execution in the host context CVSS 4.0CRITICAL 9.3
  • TI-2024-28440 Flatpak may allow access to files outside sandbox for certain apps CVSS 3.1CRITICAL 10.0
  • TI-2023-12679 TIOCLINUX can send commands outside sandbox if running on a virtual console CVSS 3.1CRITICAL 10.0
  • TI-2026-79756 Path traversal in XDG Desktop Portal allows arbitrary file access CVSS 4.0HIGH 8.8
  • TI-2026-26402 Flatpak affected by arbitrary file deletion on the host filesystem CVSS 4.0HIGH 8.7
See all 23 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences