UnratedFix available
apparmor: fix: limit the number of levels of policy namespaces
Type: advisorySources: OSV
In the Linux kernel, the following vulnerability has been resolved: apparmor: fix: limit the number of levels of policy namespaces Currently the number of policy namespaces is not bounded relying on the user namespace limit. However policy namespaces aren't strictly tied to user namespaces and it is possible to create them and nest them arbitrarily deep which can be used to exhaust system resource. Hard cap policy namespaces to the same depth as user namespaces.
- Products
- Kernel
- Affected versions
- Not specified
- Fixed versions
- 5.10.253, 5.15.203, 6.1.169, 6.12.77, 6.18.18, 6.19.8, 6.6.130
- CVEs
- CVE-2026-23405
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 6 Nov 2026, 01:46 UTC · Revision 1
Source evidence
apparmor: fix: limit the number of levels of policy namespaces
core-osv · Original sourcePublished 1 Apr 2026, 08:36 UTC
In the Linux kernel, the following vulnerability has been resolved: apparmor: fix: limit the number of levels of policy namespaces Currently the number of policy namespaces is not bounded relying on the user namespace limit. However policy namespaces aren't strictly tied to user namespaces and it is possible to create them and nest them arbitrarily deep which can be used to exhaust system resource. Hard cap policy namespaces to the same depth as user namespaces.
osv:CVE-2026-23405
Kernel
Fixed versions: 5.10.253, 5.15.203, 6.1.169, 6.6.130, 6.12.77, 6.18.18, 6.19.8
Complete source record
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"summary": "In the Linux kernel, the following vulnerability has been resolved: apparmor: fix: limit the number of levels of policy namespaces Currently the number of policy namespaces is not bounded relying on the user namespace limit. However policy namespaces aren't strictly tied to user namespaces and it is possible to create them and nest them arbitrarily deep which can be used to exhaust system resource. Hard cap policy namespaces to the same depth as user namespaces.",
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"modified": "2026-10-28T02:30:46.164485251Z",
"provider": "osv",
"references": [
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"https://nvd.nist.gov/vuln/detail/CVE-2026-23405",
"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
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"provider_metadata": {
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"related_cves": [
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"evidence": "/id"
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"security_relevant": true,
"severity_evidence": null
},
"source_id": "core-osv",
"document_id": 513990,
"published_at": "2026-04-01T08:36:35.697+00:00"
}