CVE-2026-96276
Flatpak: flatpak: arbitrary write in host context via flatpak build-init
Description
If a malicious SDK container declares an extension point with a crafted `directory` path, and a developer runs `flatpak build-init --writable-sdk --sdk-extension` with that SDK, attacker-chosen files could be written outside the working directory, since the target path is resolved via a function that allows `..` traversal.
INFO
Published Date :
Sept. 23, 2026, 3:17 p.m.
Last Modified :
Sept. 23, 2026, 4:16 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-96276
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | CRITICAL | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
Solution
- Validate SDK extension directory paths for traversal.
- Restrict file operations to the intended directory.
- Update SDK build tools to prevent path manipulation.
- Review SDK extension declarations for malicious paths.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-96276.
| URL | Resource |
|---|---|
| https://access.redhat.com/security/cve/CVE-2026-96276 | |
| https://bugzilla.redhat.com/show_bug.cgi?id=2539418 | |
| https://github.com/flatpak/flatpak/security/advisories/GHSA-8qxj-x646-phcm |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-96276 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-96276
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-96276 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-96276 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Sep. 23, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Added SSVC {'id': 'CVE-2026-96276', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-09-23T15:28:10.393280Z'} -
New CVE Received by [email protected]
Sep. 23, 2026
Action Type Old Value New Value Added Description If a malicious SDK container declares an extension point with a crafted `directory` path, and a developer runs `flatpak build-init --writable-sdk --sdk-extension` with that SDK, attacker-chosen files could be written outside the working directory, since the target path is resolved via a function that allows `..` traversal. Added CWE CWE-22 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/96xxx/CVE-2026-96276.json">CVE-2026-96276</a> Added Reference https://access.redhat.com/security/cve/CVE-2026-96276 Added Reference https://bugzilla.redhat.com/show_bug.cgi?id=2539418 Added Reference https://github.com/flatpak/flatpak/security/advisories/GHSA-8qxj-x646-phcm