ubuntu-cve-2026-33179
Vulnerability from osv_ubuntu
Published
2026-03-20 21:17
Modified
2026-05-20 15:27
Summary
Details

libfuse is the reference implementation of the Linux FUSE. From version 3.18.0 to before version 3.18.2, a NULL pointer dereference and memory leak in fuse_uring_init_queue allows a local user to crash the FUSE daemon or cause resource exhaustion. When numa_alloc_local fails during io_uring queue entry setup, the code proceeds with NULL pointers. When fuse_uring_register_queue fails, NUMA allocations are leaked and the function incorrectly returns success. Only the io_uring transport is affected; the traditional /dev/fuse path is not affected. PoC confirmed with AddressSanitizer/LeakSanitizer. This issue has been patched in version 3.18.2.

Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
N/A (UNKNOWN)
medium
References
To clipboard 

{
  "affected": [
    {
      "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"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "fuse3",
        "purl": "pkg:deb/ubuntu/fuse3@3.18.2-1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.17.4-1",
        "3.18.1-1",
        "3.18.2-1"
      ]
    }
  ],
  "aliases": [],
  "details": "libfuse is the reference implementation of the Linux FUSE. From version 3.18.0 to before version 3.18.2, a NULL pointer dereference and memory leak in fuse_uring_init_queue allows a local user to crash the FUSE daemon or cause resource exhaustion. When numa_alloc_local fails during io_uring queue entry setup, the code proceeds with NULL pointers. When fuse_uring_register_queue fails, NUMA allocations are leaked and the function incorrectly returns success. Only the io_uring transport is affected; the traditional /dev/fuse path is not affected. PoC confirmed with AddressSanitizer/LeakSanitizer. This issue has been patched in version 3.18.2.",
  "id": "UBUNTU-CVE-2026-33179",
  "modified": "2026-05-20T15:27:21Z",
  "published": "2026-03-20T21:17:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-33179"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-33179"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/libfuse/libfuse/releases/tag/fuse-3.18.2"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/libfuse/libfuse/security/advisories/GHSA-x669-v3mq-r358"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-33179"
  ]
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.