CVE-2026-33179 (GCVE-0-2026-33179)
Vulnerability from cvelistv5 – Published: 2026-03-20 20:20 – Updated: 2026-03-25 13:55
VLAI
EPSS
VEX
Title
libfuse: NULL Pointer Dereference and Memory Leak in io_uring Queue Initialization
Summary
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)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-25 13:55 UTC
CWE
- CWE-476 - NULL Pointer Dereference
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://github.com/libfuse/libfuse/security/advis… | x_refsource_CONFIRM |
| https://github.com/libfuse/libfuse/commit/7beb86c… | x_refsource_MISC |
| https://github.com/libfuse/libfuse/releases/tag/f… | x_refsource_MISC |
Impacted products
{
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-33179",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-03-25T13:55:38.887586Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-03-25T13:55:45.971Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"product": "libfuse",
"vendor": "libfuse",
"versions": [
{
"status": "affected",
"version": "\u003e= 3.18.0, \u003c 3.18.2"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "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."
}
],
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 5.5,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"version": "3.1"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-476",
"description": "CWE-476: NULL Pointer Dereference",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-03-20T20:20:09.171Z",
"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"shortName": "GitHub_M"
},
"references": [
{
"name": "https://github.com/libfuse/libfuse/security/advisories/GHSA-x669-v3mq-r358",
"tags": [
"x_refsource_CONFIRM"
],
"url": "https://github.com/libfuse/libfuse/security/advisories/GHSA-x669-v3mq-r358"
},
{
"name": "https://github.com/libfuse/libfuse/commit/7beb86c09b6ec5aab14dc25256ed8a5ad18554d7",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/libfuse/libfuse/commit/7beb86c09b6ec5aab14dc25256ed8a5ad18554d7"
},
{
"name": "https://github.com/libfuse/libfuse/releases/tag/fuse-3.18.2",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/libfuse/libfuse/releases/tag/fuse-3.18.2"
}
],
"source": {
"advisory": "GHSA-x669-v3mq-r358",
"discovery": "UNKNOWN"
},
"title": "libfuse: NULL Pointer Dereference and Memory Leak in io_uring Queue Initialization"
}
},
"cveMetadata": {
"assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"assignerShortName": "GitHub_M",
"cveId": "CVE-2026-33179",
"datePublished": "2026-03-20T20:20:09.171Z",
"dateReserved": "2026-03-17T22:16:36.720Z",
"dateUpdated": "2026-03-25T13:55:45.971Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"epss": {
"cve": "CVE-2026-33179",
"date": "2026-09-23",
"epss": "0.00197",
"percentile": "0.0968"
},
"nvd": {
"cve": {
"affected": [
{
"affectedData": [
{
"product": "libfuse",
"vendor": "libfuse",
"versions": [
{
"status": "affected",
"version": "\u003e= 3.18.0, \u003c 3.18.2"
}
]
}
],
"source": "security-advisories@github.com"
}
],
"configurations": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:a:libfuse_project:libfuse:*:*:*:*:*:*:*:*",
"matchCriteriaId": "83EF6E3E-F5F2-4CE2-B497-62493DAB2A1F",
"versionEndExcluding": "3.18.2",
"versionStartIncluding": "3.18.0",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "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."
},
{
"lang": "es",
"value": "libfuse es la implementaci\u00f3n de referencia de FUSE de Linux. Desde la versi\u00f3n 3.18.0 hasta antes de la versi\u00f3n 3.18.2, una desreferencia de puntero NULL y una fuga de memoria en fuse_uring_init_queue permiten a un usuario local bloquear el demonio FUSE o causar agotamiento de recursos. Cuando numa_alloc_local falla durante la configuraci\u00f3n de la entrada de la cola io_uring, el c\u00f3digo procede con punteros NULL. Cuando fuse_uring_register_queue falla, las asignaciones NUMA se filtran y la funci\u00f3n devuelve \u00e9xito incorrectamente. Solo el transporte io_uring se ve afectado; la ruta tradicional /dev/fuse no se ve afectada. PoC confirmado con AddressSanitizer/LeakSanitizer. Este problema ha sido parcheado en la versi\u00f3n 3.18.2."
}
],
"id": "CVE-2026-33179",
"lastModified": "2026-06-17T10:37:05.247",
"metrics": {
"cvssMetricV31": [
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 5.5,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"version": "3.1"
},
"exploitabilityScore": 1.8,
"impactScore": 3.6,
"source": "security-advisories@github.com",
"type": "Secondary"
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-33179",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-03-25T13:55:38.887586Z",
"version": "2.0.3"
}
}
]
},
"published": "2026-03-20T21:17:16.593",
"references": [
{
"source": "security-advisories@github.com",
"tags": [
"Patch"
],
"url": "https://github.com/libfuse/libfuse/commit/7beb86c09b6ec5aab14dc25256ed8a5ad18554d7"
},
{
"source": "security-advisories@github.com",
"tags": [
"Product",
"Release Notes"
],
"url": "https://github.com/libfuse/libfuse/releases/tag/fuse-3.18.2"
},
{
"source": "security-advisories@github.com",
"tags": [
"Vendor Advisory"
],
"url": "https://github.com/libfuse/libfuse/security/advisories/GHSA-x669-v3mq-r358"
}
],
"sourceIdentifier": "security-advisories@github.com",
"vulnStatus": "Analyzed",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-476"
}
],
"source": "security-advisories@github.com",
"type": "Secondary"
}
]
}
},
"redhat_vex": {
"aggregate_severity": "Moderate",
"current_release_date": "2026-06-28T06:29:36+00:00",
"cve": "CVE-2026-33179",
"id": "CVE-2026-33179",
"initial_release_date": "2026-03-20T20:20:09.171000+00:00",
"product_status:known_affected": "5",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "libfuse: libfuse: Denial of Service via NULL pointer dereference and memory leak",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33179.json",
"version": "3"
},
"suse_vex": {
"aggregate_severity": "moderate",
"current_release_date": "2026-03-24T00:24:38Z",
"cve": "CVE-2026-33179",
"id": "CVE-2026-33179",
"initial_release_date": "2026-03-24T00:24:38Z",
"product_status:known_not_affected": "193",
"source": "SUSE CSAF VEX",
"status": "interim",
"title": "SUSE CVE CVE-2026-33179",
"url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-33179.json",
"version": "2"
},
"vulnrichment": {
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-33179",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-03-25T13:55:38.887586Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-03-25T13:55:42.459Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"product": "libfuse",
"vendor": "libfuse",
"versions": [
{
"status": "affected",
"version": "\u003e= 3.18.0, \u003c 3.18.2"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "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."
}
],
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 5.5,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"version": "3.1"
}
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-476",
"description": "CWE-476: NULL Pointer Dereference",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-03-20T20:20:09.171Z",
"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"shortName": "GitHub_M"
},
"references": [
{
"name": "https://github.com/libfuse/libfuse/security/advisories/GHSA-x669-v3mq-r358",
"tags": [
"x_refsource_CONFIRM"
],
"url": "https://github.com/libfuse/libfuse/security/advisories/GHSA-x669-v3mq-r358"
},
{
"name": "https://github.com/libfuse/libfuse/commit/7beb86c09b6ec5aab14dc25256ed8a5ad18554d7",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/libfuse/libfuse/commit/7beb86c09b6ec5aab14dc25256ed8a5ad18554d7"
},
{
"name": "https://github.com/libfuse/libfuse/releases/tag/fuse-3.18.2",
"tags": [
"x_refsource_MISC"
],
"url": "https://github.com/libfuse/libfuse/releases/tag/fuse-3.18.2"
}
],
"source": {
"advisory": "GHSA-x669-v3mq-r358",
"discovery": "UNKNOWN"
},
"title": "libfuse: NULL Pointer Dereference and Memory Leak in io_uring Queue Initialization"
}
},
"cveMetadata": {
"assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
"assignerShortName": "GitHub_M",
"cveId": "CVE-2026-33179",
"datePublished": "2026-03-20T20:20:09.171Z",
"dateReserved": "2026-03-17T22:16:36.720Z",
"dateUpdated": "2026-03-25T13:55:45.971Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
Loading…
Loading…
Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
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.
Loading…
Loading…
The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
Loading…
Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
Loading…