UBUNTU-CVE-2026-33150

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Source
https://ubuntu.com/security/CVE-2026-33150
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-33150.json
JSON Data
https://api.osv.dev/v1/vulns/UBUNTU-CVE-2026-33150
Upstream
Withdrawn
2026-07-28T18:33:22Z
Published
2026-03-20T21:17:00Z
Modified
2026-07-28T21:28:01Z
Severity
  • 7.8 (High) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H CVSS Calculator
  • 7.8 (High) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H CVSS Calculator
  • Ubuntu - medium
Summary
[none]
Details

libfuse is the reference implementation of the Linux FUSE. From version 3.18.0 to before version 3.18.2, a use-after-free vulnerability in the io_uring subsystem of libfuse allows a local attacker to crash FUSE filesystem processes and potentially execute arbitrary code. When io_uring thread creation fails due to resource exhaustion (e.g., cgroup pids.max), fuse_uring_start() frees the ring pool structure but stores the dangling pointer in the session state, leading to a use-after-free when the session shuts down. The trigger is reliable in containerized environments where cgroup pids.max limits naturally constrain thread creation. This issue has been patched in version 3.18.2.

References

Affected packages

Ubuntu:26.04:LTS / fuse3

Package

Name
fuse3
Purl
pkg:deb/ubuntu/fuse3?arch=source&distro=resolute

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

3.*
3.17.4-1
3.18.1-1
3.18.2-1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "fuse",
            "binary_version": "3.18.2-1"
        },
        {
            "binary_name": "fuse3",
            "binary_version": "3.18.2-1"
        },
        {
            "binary_name": "libfuse3-4",
            "binary_version": "3.18.2-1"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-33150.json"