CVE-2026-33150

Use After Free in libfuse

HIGH
7.8
CVSS Score
Published: March 20, 2026 at 08:20 PM UTC
Updated: July 15, 2026 at 02:20 AM UTC
3 products affected across 3 vendorsLibfuseEnterprise LinuxLibfuse

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Severity
HIGH7.8
Exploit prediction
EPSS 0.3%
SSVC
No known exploit

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

3.18.0 ≤ v < 3.18.2
Affected range stops below 3.18.2, so it looks safe — our inference, not a vendor statement
v < 3.18.2
Affected range stops below 3.18.2, so it looks safe — our inference, not a vendor statement
Vendor states this is fixed in 7 (unaffected)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (6)

x_refsource_CONFIRMVendor Advisory
Source: cverecord
https://github.com/libfuse/libfuse/security/advisories/GHSA-qxv7-xrc2-qmfx
x_refsource_MISCProductRelease Notes
Source: cverecord
https://github.com/libfuse/libfuse/releases/tag/fuse-3.18.2
Source: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
https://access.redhat.com/security/cve/CVE-2026-33150
Source: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
https://bugzilla.redhat.com/show_bug.cgi?id=2449771

SSVC — Action Prioritization

SSVCNo known exploitNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.8HIGHGitHub_M
Attack Vector
LOCAL
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-416CWE-825

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