Local code execution via dangling io_uring pool
Published Mar 20, 2026 · Updated Mar 20, 2026
Use-after-free in libfuse 3.18.0 through 3.18.1 allows local users to crash FUSE filesystem processes or execute arbitrary code. On thread-creation failure, fuse_uring_start() destroys the ring pool but leaves its address in se->uring.pool, which shutdown cleanup later dereferences. Only the io_uring transport is affected, and exploitation requires local access plus a thread-creation failure such as cgroup PID exhaustion.
Summary
What happened
Use-after-free in libfuse 3.18.0 through 3.18.1 allows local users to crash FUSE filesystem processes or execute arbitrary code. On thread-creation failure, fuse_uring_start() destroys the ring pool but leaves its address in se->uring.pool, which shutdown cleanup later dereferences. Only the io_uring transport is affected, and exploitation requires local access plus a thread-creation failure such as cgroup PID exhaustion.
The record
- CVE
- CVE-2026-33150
- Published
- Mar 20, 2026
- Updated
- Mar 20, 2026
- Vendor
- libfuse
- Product
- libfuse
- Classifications
- CWE-825, CWE-416
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Mar 20, 2026CVE publishedPublication date reported by the CVE source.
- Mar 20, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=>= 3.18.0, < 3.18.2
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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