CVE-2026-97026

Installation denial of service via writable child repositories

Published Sep 28, 2026 · Updated Sep 30, 2026

Flatpak on Red Hat Enterprise Linux 7, 8, 9, and 10 lets local users disrupt app installation through writable cache directories. During a client pull, flatpak_allocate_tmpdir creates repo- and child-oci- directories beneath the user cache with mode 0777, allowing another local account to alter their contents before system-helper deployment. Exposure requires a multi-user host, a permissive umask, and an affected libflatpak caller; altered app or runtime content fails signature or digest verification rather than installing.

CVSS severity3.9
Low
EPSS probability0.11%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Get started

Summary

What happened

Flatpak on Red Hat Enterprise Linux 7, 8, 9, and 10 lets local users disrupt app installation through writable cache directories. During a client pull, flatpak_allocate_tmpdir creates repo- and child-oci- directories beneath the user cache with mode 0777, allowing another local account to alter their contents before system-helper deployment. Exposure requires a multi-user host, a permissive umask, and an affected libflatpak caller; altered app or runtime content fails signature or digest verification rather than installing.

The record

CVE
CVE-2026-97026
Published
Sep 28, 2026
Updated
Sep 30, 2026
Vendor
Commonhaus Foundation
Product
Red Hat Enterprise Linux 10
Classifications
CWE-378, T1499
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 28, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 30, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Commonhaus Foundation · Red Hat Enterprise Linux 10Affected versions are unavailable in this record.
Commonhaus Foundation · Red Hat Enterprise Linux 8Affected versions are unavailable in this record.
Commonhaus Foundation · Red Hat Enterprise Linux 7Affected versions are unavailable in this record.
Commonhaus Foundation · Red Hat Enterprise Linux 9Affected versions are unavailable in this record.

Published CVSS scores

2.4FlatpakCVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:P/VC:L/VI:N/VA:L/SC:N/SI:N/SA:N
3.9Red HatCVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-378Creation of Temporary File With Insecure Permissions
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Get started to see how Hinoki identifies affected software and validates exploitability in your environment.

Get started