Directory Traversal Vulnerability in Flatpak SDK by Red Hat
CVE-2026-96276

9.8CRITICAL

Key Information:

Vendor

Red Hat
Status
Red Hat Enterprise Linux 10
Red Hat Enterprise Linux 7
Red Hat Enterprise Linux 8
Red Hat Enterprise Linux 9
Vendor
CVE Published:
23 September 2026

What is CVE-2026-96276?

In the Flatpak SDK by Red Hat, a vulnerability exists that allows malicious SDK containers to declare an extension point with a specially crafted directory path. When developers execute flatpak build-init --writable-sdk --sdk-extension with these SDKs, it may lead to attacker-controlled files being written outside the designated working directory. This occurs due to a resolution function that permits directory traversal using .., potentially compromising system security and integrity.

References

https://access.redhat.com/security/cve/CVE-2026-96276
vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2539418
issue-trackingx_refsource_REDHAT
https://github.com/flatpak/flatpak/security/advisories/GH...

CVSS V3.1

Score:
9.8
Severity:
CRITICAL
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Upstream acknowledges Sebastian Wick as the original reporter.
.