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TI-2026-61622 Aliases CVE-2026-90616GHSA-vhx5-8pfj-7wrv

In Flatpak before 1.18.1, a malicious sandboxed app can obtain arbitrary read and write…

Priority LOW 34CWE-61Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
None
Attack complexity
High
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 14 fixed, 1 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 obtain arbitrary read and write access to files on the host, which can be escalated to arbitrary code execution on the host, a different vulnerability than CVE-2026-76925. Flatpak creates a few app data directories (e.g., /var/cache, /var/data, /var/config, and /var/tmp) in every sandbox on every app launch where, in some cases, components of the path are attacker-controlled. Missing symlink protection can redirect the directories. Some of these directories are bind-mounted by Flatpak by passing the path (e.g., /home/user/.var/app/APP_ID/cache/tmp), which contains attacker-controlled directories (tmp) to bwrap --bind SRC DST. bwrap passes the path on to the kernel, which then follows symlinks. A malicious symlink can point to arbitrary locations on the host and it will become mounted inside the sandbox.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00176 7th percentileScored 2026-11-07
Fix Partial Flatpak (Flatpak): 1.18.1Red Hat: 8 advisoriesRed Hat: 14 fixed, 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

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

Red Hat 8 advisories

  • RHSA-2026:95493 Released 2026-11-05 · Red Hat rating Important
    flatpak security update
    • Red Hat Enterprise Linux AppStream AUS (v.8.6) flatpak-1.12.9-1.el8_6.1, flatpak-libs-1.12.9-1.el8_6.1, flatpak-selinux-1.12.9-1.el8_6.1 +1
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) flatpak-1.12.9-1.el8_6.1, flatpak-libs-1.12.9-1.el8_6.1, flatpak-selinux-1.12.9-1.el8_6.1 +1
  • RHSA-2026:92221 Released 2026-11-02 · Red Hat rating Important
    flatpak security update
    • Red Hat Enterprise Linux AppStream EUS (v. 10.0) flatpak-1.16.0-5.el10_0.6, flatpak-libs-1.16.0-5.el10_0.6, flatpak-selinux-1.16.0-5.el10_0.6 +1
    • Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) flatpak-devel-1.16.0-5.el10_0.6
  • RHSA-2026:92369 Released 2026-10-29 · Red Hat rating Important
    flatpak security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.2) flatpak-1.12.7-5.el9_2.5, flatpak-libs-1.12.7-5.el9_2.5, flatpak-selinux-1.12.7-5.el9_2.5 +1
Show 5 more Red Hat advisories
  • RHSA-2026:90364 Released 2026-10-26 · Red Hat rating Important
    flatpak security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.4) flatpak-1.12.9-3.el9_4.5, flatpak-libs-1.12.9-3.el9_4.5, flatpak-selinux-1.12.9-3.el9_4.5 +1
  • RHSA-2026:89733 Released 2026-10-26 · Red Hat rating Important
    flatpak security update
    • Red Hat CodeReady Linux Builder EUS (v.9.6) flatpak-1.12.9-4.el9_6.5, flatpak-devel-1.12.9-4.el9_6.5, flatpak-session-helper-1.12.9-4.el9_6.5
    • Red Hat Enterprise Linux AppStream EUS (v.9.6) flatpak-1.12.9-4.el9_6.5, flatpak-libs-1.12.9-4.el9_6.5, flatpak-selinux-1.12.9-4.el9_6.5 +1
  • RHSA-2026:80687 Released 2026-10-12 · Red Hat rating Important
    flatpak security update
    • Red Hat Enterprise Linux AppStream (v. 8) flatpak-1.12.9-7.el8_10, flatpak-libs-1.12.9-7.el8_10, flatpak-selinux-1.12.9-7.el8_10 +1
    • Red Hat Enterprise Linux CRB (v. 8) flatpak-1.12.9-7.el8_10, flatpak-devel-1.12.9-7.el8_10, flatpak-session-helper-1.12.9-7.el8_10
  • RHSA-2026:80497 Released 2026-10-12 · Red Hat rating Important
    flatpak security update
    • Red Hat Enterprise Linux AppStream (v. 9) flatpak-1.12.9-4.el9_8.4, flatpak-libs-1.12.9-4.el9_8.4, flatpak-selinux-1.12.9-4.el9_8.4 +1
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) flatpak-1.12.9-4.el9_8.4, flatpak-devel-1.12.9-4.el9_8.4, flatpak-session-helper-1.12.9-4.el9_8.4
  • RHSA-2026:80498 Released 2026-10-12 · Red Hat rating Important
    flatpak security update
    • Red Hat Enterprise Linux AppStream (v. 10) flatpak-1.16.0-9.el10_2.4, flatpak-libs-1.16.0-9.el10_2.4, flatpak-selinux-1.16.0-9.el10_2.4 +1
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) flatpak-devel-1.16.0-9.el10_2.4

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 7AffectedNo fix yet
Red Hat CodeReady Linux Builder EUS (v.9.6)Fixed RHSA-2026:89733
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:80498
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2026:80687
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:80497
Red Hat Enterprise Linux AppStream AUS (v.8.6)Fixed RHSA-2026:95493
Red Hat Enterprise Linux AppStream E4S (v.9.2)Fixed RHSA-2026:92369
Red Hat Enterprise Linux AppStream E4S (v.9.4)Fixed RHSA-2026:90364
Red Hat Enterprise Linux AppStream EUS (v. 10.0)Fixed RHSA-2026:92221
Red Hat Enterprise Linux AppStream EUS (v.9.6)Fixed RHSA-2026:89733
Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)Fixed RHSA-2026:95493
Red Hat Enterprise Linux CRB (v. 8)Fixed RHSA-2026:80687
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2026:80498
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2026:80497
Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0)Fixed RHSA-2026:92221

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-90616
  2. 2026-10-03 Alias added: GHSA-vhx5-8pfj-7wrv
  3. 2026-10-12 Fix available: RHSA-2026:80498 · Red Hat
  4. 2026-10-12 Fix available: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) · Red Hat
  5. 2026-10-12 Fix available: RHSA-2026:80497 · Red Hat
  6. 2026-10-12 Fix available: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) · Red Hat
  7. 2026-10-12 Fix available: RHSA-2026:80687 · Red Hat
  8. 2026-10-13 Fix available: Red Hat Enterprise Linux AppStream (v. 8), Red Hat Enterprise Linux CRB (v. 8) · Red Hat
  9. 2026-10-26 Fix available: RHSA-2026:89733 · Red Hat
  10. 2026-10-26 Fix available: Red Hat CodeReady Linux Builder EUS (v.9.6), Red Hat Enterprise Linux AppStream EUS (v.9.6) · Red Hat
  11. 2026-10-27 Fix available: Red Hat Enterprise Linux AppStream E4S (v.9.4) · Red Hat
  12. 2026-10-29 Fix available: RHSA-2026:90364 · Red Hat
  13. 2026-10-30 Fix available: RHSA-2026:92369 · Red Hat
  14. 2026-10-30 Fix available: Red Hat Enterprise Linux AppStream E4S (v.9.2) · Red Hat
  15. 2026-11-02 Fix available: RHSA-2026:92221 · Red Hat
  16. 2026-11-02 Fix available: Red Hat Enterprise Linux AppStream EUS (v. 10.0), Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0) · Red Hat
  17. 2026-11-05 Fix available: Red Hat Enterprise Linux AppStream AUS (v.8.6), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) · Red Hat
  18. 2026-11-06 Fix available: RHSA-2026:95493 · Red Hat

References

Other 2

  • 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