FKIE_CVE-2021-46945
Vulnerability from fkie_nvd - Published: 2024-02-27 19:04 - Updated: 2026-06-17 04:15
Severity
Summary
In the Linux kernel, the following vulnerability has been resolved:
ext4: always panic when errors=panic is specified
Before commit 014c9caa29d3 ("ext4: make ext4_abort() use
__ext4_error()"), the following series of commands would trigger a
panic:
1. mount /dev/sda -o ro,errors=panic test
2. mount /dev/sda -o remount,abort test
After commit 014c9caa29d3, remounting a file system using the test
mount option "abort" will no longer trigger a panic. This commit will
restore the behaviour immediately before commit 014c9caa29d3.
(However, note that the Linux kernel's behavior has not been
consistent; some previous kernel versions, including 5.4 and 4.19
similarly did not panic after using the mount option "abort".)
This also makes a change to long-standing behaviour; namely, the
following series commands will now cause a panic, when previously it
did not:
1. mount /dev/sda -o ro,errors=panic test
2. echo test > /sys/fs/ext4/sda/trigger_fs_error
However, this makes ext4's behaviour much more consistent, so this is
a good thing.
References
Impacted products
| Vendor | Product | Version | |
|---|---|---|---|
| linux | linux_kernel | * | |
| linux | linux_kernel | * |
{
"affected": [
{
"affectedData": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"fs/ext4/super.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "64e1eebe2131183174f4fbb6b1491355f96c6cde",
"status": "affected",
"version": "014c9caa29d3a44e0de695c99ef18bec3e887d52",
"versionType": "git"
},
{
"lessThan": "1e9ea8f4637026b8e965128953f2da061ccae9c4",
"status": "affected",
"version": "014c9caa29d3a44e0de695c99ef18bec3e887d52",
"versionType": "git"
},
{
"lessThan": "ac2f7ca51b0929461ea49918f27c11b680f28995",
"status": "affected",
"version": "014c9caa29d3a44e0de695c99ef18bec3e887d52",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"fs/ext4/super.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "5.11"
},
{
"lessThan": "5.11",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.11.*",
"status": "unaffected",
"version": "5.11.20",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.12.*",
"status": "unaffected",
"version": "5.12.3",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "5.13",
"versionType": "original_commit_for_fix"
}
]
}
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"configurations": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "EFB425F0-C28C-4B44-8B4C-AD512AA832DE",
"versionEndExcluding": "5.11.20",
"versionStartIncluding": "5.11.0",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "C3814FA3-8141-4313-A852-8C4212BE12AD",
"versionEndExcluding": "5.12.3",
"versionStartIncluding": "5.12.0",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\next4: always panic when errors=panic is specified\n\nBefore commit 014c9caa29d3 (\"ext4: make ext4_abort() use\n__ext4_error()\"), the following series of commands would trigger a\npanic:\n\n1. mount /dev/sda -o ro,errors=panic test\n2. mount /dev/sda -o remount,abort test\n\nAfter commit 014c9caa29d3, remounting a file system using the test\nmount option \"abort\" will no longer trigger a panic. This commit will\nrestore the behaviour immediately before commit 014c9caa29d3.\n(However, note that the Linux kernel\u0027s behavior has not been\nconsistent; some previous kernel versions, including 5.4 and 4.19\nsimilarly did not panic after using the mount option \"abort\".)\n\nThis also makes a change to long-standing behaviour; namely, the\nfollowing series commands will now cause a panic, when previously it\ndid not:\n\n1. mount /dev/sda -o ro,errors=panic test\n2. echo test \u003e /sys/fs/ext4/sda/trigger_fs_error\n\nHowever, this makes ext4\u0027s behaviour much more consistent, so this is\na good thing."
},
{
"lang": "es",
"value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: ext4: siempre entra en p\u00e1nico cuando se especifica errores=panic Antes del commit 014c9caa29d3 (\"ext4: make ext4_abort() use __ext4_error()\"), la siguiente serie de comandos desencadenar\u00eda un p\u00e1nico: 1. mount /dev/sda -o ro,errors=panic test 2. mount /dev/sda -o remount,abort test Despu\u00e9s de el commit 014c9caa29d3, volver a montar un sistema de archivos utilizando la opci\u00f3n de montaje de prueba \"abort\" ya no provocar\u00e1 p\u00e1nico . Esta confirmaci\u00f3n restaurar\u00e1 el comportamiento inmediatamente anterior a el commit 014c9caa29d3. (Sin embargo, tenga en cuenta que el comportamiento del kernel de Linux no ha sido consistente; algunas versiones anteriores del kernel, incluidas 5.4 y 4.19, tampoco entraron en p\u00e1nico despu\u00e9s de usar la opci\u00f3n de montaje \"abortar\".) Esto tambi\u00e9n supone un cambio en el comportamiento de larga data; es decir, los siguientes comandos de la serie ahora causar\u00e1n p\u00e1nico, cuando antes no lo hac\u00edan: 1. mount /dev/sda -o ro,errors=panic test 2. echo test \u0026gt; /sys/fs/ext4/sda/trigger_fs_error Sin embargo, Esto hace que el comportamiento de ext4 sea mucho m\u00e1s consistente, por lo que es algo bueno."
}
],
"id": "CVE-2021-46945",
"lastModified": "2026-06-17T04:15:56.467",
"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": "nvd@nist.gov",
"type": "Primary"
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2021-46945",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2024-06-28T17:01:37.364142Z",
"version": "2.0.3"
}
}
]
},
"published": "2024-02-27T19:04:06.190",
"references": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/1e9ea8f4637026b8e965128953f2da061ccae9c4"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/64e1eebe2131183174f4fbb6b1491355f96c6cde"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/ac2f7ca51b0929461ea49918f27c11b680f28995"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/1e9ea8f4637026b8e965128953f2da061ccae9c4"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/64e1eebe2131183174f4fbb6b1491355f96c6cde"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/ac2f7ca51b0929461ea49918f27c11b680f28995"
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"vulnStatus": "Modified",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "NVD-CWE-noinfo"
}
],
"source": "nvd@nist.gov",
"type": "Primary"
}
]
}
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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.
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