CVE-2026-96807

flatpak: Flatpak: Low integrity or availability impact via symlink manipulation

Published Sep 23, 2026 CVSS 3.1 · 4 Medium EPSS < 1% KEV · Not listed
Description
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.

Remediation

Vendor Solution

The issue has been fixed in version 1.18.1 by commits: * e13dfed https://github.com/flatpak/flatpak/commit/e13dfeda330625d2fecc3a54672dfd4dc9c83a5c "common: Fix return value and typos in flatpak_switch_symlink_and_remove" * f6c8fb5 https://github.com/flatpak/flatpak/commit/f6c8fb5fdb3737e2f45068afe12c4bf1d808fd55 "common: Use fd-based operations in flatpak_switch_symlink_and_remove" * 76c9296 https://github.com/flatpak/flatpak/commit/76c9296b6780ca67f44cf67f0823f086d692a592 "run: Harden regenerate_ld_cache against symlink attacks" For LTS operating system distributions, backports of these changes are available in the flatpak-1.16.x branch. Please note that cherry-picked libglnx changes "chase: Add internal glnx_chaseat_full for a strategic callback" and "chase: Add glnx_chase_and_mkdirat" are also required.

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Title Flatpak LD Cache Symlink Attack flatpak: Flatpak: Low integrity or availability impact via symlink manipulation
Weaknesses CWE-22
References
Metrics threat_severity

None

threat_severity

Moderate

Type Values Removed Values Added
Title Flatpak LD Cache Symlink Attack
Type Values Removed Values Added
Description 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.
First Time appeared Flatpak
Flatpak flatpak
Weaknesses CWE-61
CPEs cpe:2.3:a:flatpak:flatpak:*:*:*:*:*:*:*:*
Vendors & Products Flatpak
Flatpak flatpak
References
Metrics cvssV3_1

{'score': 4, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:L'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
mitre
Published
Updated
Sep 26, 2026, 10:51 PM
Reserved
Sep 23, 2026, 4:54 PM
Status
Awaiting Analysis
Published
Sep 23, 2026, 5:17 PM
Modified
Sep 26, 2026, 11:16 PM
Severity
Moderate
Public date
Sep 23, 2026, 4:54 PM