CVE-2026-87766CWE-59

CVE-2026-87766

High · published September 9, 2026

CVSS v3.1
8.8
EPSS
0%
Percentile
5.7
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
8.8 · HIGH
Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00168 · 5.7th percentile
Weakness
CWE-59 · Improper Link Resolution Before File Access ('Link Following')
Published
2026-09-09T13:17Z
References (18)
https://access.redhat.com/errata/RHSA-2026:85306 · [email protected]https://access.redhat.com/errata/RHSA-2026:85308 · [email protected]https://access.redhat.com/errata/RHSA-2026:85309 · [email protected]https://access.redhat.com/errata/RHSA-2026:85312 · [email protected]https://access.redhat.com/errata/RHSA-2026:85313 · [email protected]https://access.redhat.com/errata/RHSA-2026:85317 · [email protected]https://access.redhat.com/errata/RHSA-2026:85319 · [email protected]https://access.redhat.com/errata/RHSA-2026:85322 · [email protected]https://access.redhat.com/errata/RHSA-2026:85324 · [email protected]https://access.redhat.com/errata/RHSA-2026:85325 · [email protected]https://access.redhat.com/security/cve/CVE-2026-87766 · [email protected]https://bugs.debian.org/1145655 · [email protected]https://bugzilla.redhat.com/show_bug.cgi?id=2530542 · [email protected]https://github.com/containers/bubblewrap/releases/tag/v0.12.0 · [email protected]https://github.com/containers/bubblewrap/security/advisories/GHSA-pxhw-h44j-8pfx · [email protected]https://www.openwall.com/lists/oss-security/2026/08/27/7 · [email protected]http://www.openwall.com/lists/oss-security/2026/09/09/3 · af854a3a-2127-422b-91ae-364da2661108http://www.openwall.com/lists/oss-security/2026/09/22/23 · af854a3a-2127-422b-91ae-364da2661108
EPSS history
Timeline
  • 10 SEP 03:18Z
    EPSS moved — → 0%
    epss
  • 09 SEP 08:34Z
    Bubblewrap: bubblewrap: symlink traversal via /oldroot allows writing files outside sandbox during setup
    cvelistv5