CVE-2026-96276

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.

Overview

State: PUBLISHED
Assigner (CNA): redhat
CVSS severity: —
CVSS score: —
CVSS vector: —
Effective score: 9.8 / 10 CRITICAL source: NVD
CWE(s): CWE-22
Reserved: 2026-09-22
Published: 2026-09-23 15:01 UTC
Last updated: 2026-09-23 15:28 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/96xxx/CVE-2026-96276.json

NVD triage scoring NVD CVE 2.0

Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.

NVD published: 2026-09-23 15:17:32 UTC
NVD last modified: 2026-09-23 19:40:10 UTC
NVD CVSS v3.1: 9.8 / 10 CRITICAL source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
NVD CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Exploitability subscore: 3.9 / 10
Impact subscore: 5.9 / 10

European Union Vulnerability Database ENISA EUVD

ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.

EUVD ID: EUVD-2026-85343
Assigner: redhat
Published: Sep 23, 2026, 3:01:49 PM
Updated: Sep 23, 2026, 3:28:23 PM
EUVD base score (CVSS 3.1): 9.8 / 10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EUVD-reported EPSS: 0.0000

ENISA 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.

EUVD references (3)

Affected products (4)

Vendor	Product	Versions	Platforms
Red Hat	Red Hat Enterprise Linux 10	—	—
Red Hat	Red Hat Enterprise Linux 7	—	—
Red Hat	Red Hat Enterprise Linux 8	—	—
Red Hat	Red Hat Enterprise Linux 9	—	—

Vendor references (3)

References embedded in the original CVE record by the assigning CNA.

https://access.redhat.com/security/cve/CVE-2026-96276 vdb-entryx_refsource_REDHAT
RHBZ#2539418 issue-trackingx_refsource_REDHAT
https://github.com/flatpak/flatpak/security/advisories/GHSA-8qxj-x646-phcm

Web references (0)

DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.

No web references attached yet.

NVD-tagged references (3)

Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.

https://access.redhat.com/security/cve/CVE-2026-96276 secalert@redhat.com
https://bugzilla.redhat.com/show_bug.cgi?id=2539418 secalert@redhat.com
https://github.com/flatpak/flatpak/security/advisories/GHSA-8qxj-x646-phcm secalert@redhat.com

Remediations (10)

CVE-2026-96276 - Vulnerability Details - OpenCVE

web:app.opencve.io

A malicious SDK container can declare an extension point with a crafted directory path. When a developer runs flatpak build-init with the --writable-sdk and --sdk-extension flags, the path‑resolution function does not sanitize the input and allows .. traversal, enabling attacker‑chosen files to be written outside the working directory. This flaw permits arbitrary file writes in the host ...

2026-09-24 11:44 UTC
Security Update Guide - Microsoft Security Response Center

web:msrc.microsoft.com

Security Update Guide - Microsoft Security Response Center

2026-09-24 11:44 UTC
CVE-2026-96276 - security-tracker.debian.org

web:security-tracker.debian.org

Vulnerable and fixed packages The table below lists information on source packages.

2026-09-24 11:44 UTC
Microsoft Patch Tracker (September 2026): Exploit-Ranked | Senserva

web:senserva.com

Every Microsoft security patch (KB) and the CVEs it fixes, with severity, CVSS, and CISA KEV status. Cross-linked to the CVE reference.

2026-09-24 11:44 UTC
Description of the security update for Office 2016: August 11, 2026 ...

web:support.microsoft.com

Be aware that the update in the Microsoft Download Center applies to the Microsoft Installer (.msi)-based edition of Office 2016. It doesn't apply to the Office 2016 Click-to-Run editions, such as Microsoft Office 365 Home. (See What version of Office am I using?) How to get and install the update Method 1: Microsoft Update This update is available from Microsoft Update. When you turn on ...

2026-09-24 11:44 UTC
SAP Security Patch Day - June 2026

web:support.sap.com

SAP security Patch Day Bulletin This post shares the information on security notes that remediate vulnerabilities discovered in SAP products. SAP strongly recommends that the customer visits the support portal and applies patches on priority to protect their SAP landscape. On 9th of June 2026 , SAP security patch day saw the release of 15 new security notes.

2026-09-24 11:44 UTC
June 2026 Patch Tuesday: Updates and Analysis | CrowdStrike

web:www.crowdstrike.com

Microsoft patches 206 vulnerabilities in June 2026 Patch Tuesday, including three publicly disclosed zero-days.

2026-09-24 11:44 UTC
Oracle Critical Patch Update Advisory - July 2026

web:www.oracle.com

This Critical Patch Update contains 1448 new security patches across the product families listed below. Please note that a My Oracle Support (MOS) note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at July 2026 Critical Patch Update: Executive Summary and Analysis.

2026-09-24 11:44 UTC
Oracle Critical Security Patch Update Advisory - June 2026

web:www.oracle.com

Additional CVEs addressed are: The patch for CVE - 2026 -34481 also addresses CVE - 2026 -34477, CVE - 2026 -34478, CVE - 2026 -34479, and CVE - 2026 -34480. Oracle Fusion Middleware Risk Matrix This Critical Security Patch Update contains 106 new security patches for Oracle Fusion Middleware. 53 of these vulnerabilities may be remotely exploitable without authentication, i.e., may be exploited over a ...

2026-09-24 11:44 UTC
CVE-2026-6276 Common Vulnerabilities and Exposures | SUSE

web:www.suse.com

Secure your Linux systems from CVE - 2026 -6276. Stay ahead of potential threats with the latest security updates from SUSE.

2026-09-24 11:44 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-96276.json.

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