A flaw was found in bubblewrap. During sandbox setup, creating files or directories under the new root can follow a parent symlink onto the host via /oldroot, writing attacker-chosen paths outside the sandbox as the launching user. This happens before the sandboxed process starts. This issue is GHSA-pxhw-h44j-8pfx. It is fixed in bubblewrap 0.12.0.
https://www.openwall.com/lists/oss-security/2026/08/27/7
https://github.com/containers/bubblewrap/security/advisories/GHSA-pxhw-h44j-8pfx
https://github.com/containers/bubblewrap/releases/tag/v0.12.0
https://bugzilla.redhat.com/show_bug.cgi?id=2530542
https://bugs.debian.org/1145655