CVE-2026-33150

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.

Database specific

{
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-416"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33150.json"
}

References

Affected packages

Git / github.com/libfuse/libfuse

Affected ranges

Type

GIT

Repo

https://github.com/libfuse/libfuse

Events

Introduced

9157d99f17384f362c65b02cec065e0aec5f0b56

Fixed

033844748010a3b8265bf1c90b9ae8ffe4cd9ca7

Fixed

49fcd891a58f622c098e2ca67d66086f7b213836

Database specific

Show details

{
    "cpe": "cpe:2.3:a:libfuse_project:libfuse:*:*:*:*:*:*:*:*",
    "extracted_events": [
        {
            "introduced": "3.18.0"
        },
        {
            "fixed": "3.18.2"
        }
    ],
    "source": [
        "CPE_RANGE",
        "REFERENCES"
    ]
}

Affected versions

fuse-3.*

fuse-3.18.0

fuse-3.18.1

Database specific

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-33150.json"

vanir_signatures

[
    {
        "deprecated": false,
        "digest": {
            "line_hashes": [
                "299934566000463084493258070924523487637",
                "110030752691638793047042537792243545334",
                "146088484175563655392658876407671317044",
                "227170435765217123882477481264954327236",
                "111523425814923684263911035124315833850"
            ],
            "threshold": 0.9
        },
        "id": "CVE-2026-33150-740b10bb",
        "signature_type": "Line",
        "signature_version": "v1",
        "source": "https://github.com/libfuse/libfuse/commit/49fcd891a58f622c098e2ca67d66086f7b213836",
        "target": {
            "file": "lib/fuse_uring.c"
        }
    },
    {
        "deprecated": false,
        "digest": {
            "function_hash": "191538989541291180850150979726671951433",
            "length": 740
        },
        "id": "CVE-2026-33150-d198a3cf",
        "signature_type": "Function",
        "signature_version": "v1",
        "source": "https://github.com/libfuse/libfuse/commit/49fcd891a58f622c098e2ca67d66086f7b213836",
        "target": {
            "file": "lib/fuse_uring.c",
            "function": "fuse_uring_start"
        }
    }
]

vanir_signatures_modified

"2026-08-12T15:32:36Z"