Vulnerability-Lookup

FKIE_CVE-2026-23405

Vulnerability from fkie_nvd - Published: 2026-04-01 09:16 - Updated: 2026-04-24 18:40

Severity ?

5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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.

References

URL	Tags
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/306039414932c80f8420695a24d4fe10c84ccfb2	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/3f8699b3ee0c04b4b9bc27b82cd89a40e81e1d2e	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/6b396cc2f0365e684fc1d3547d18ef79fcee225d	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/7b6495ead2c611647f6b11441a852324e3eb8616	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/853ce31ca72097d23991a06876a2ccb5cb64b603	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/87d0cecc900e55d55fc4dbfb43ac93e269c7a5b3	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/b1226e37eb3754d389721c135db6107db94c7a72	Patch
416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/d42b2b6bb77ca40ee34ab74ad79305840b5f315d	Patch

Impacted products

Vendor	Product	Version
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	*
linux	linux_kernel	2.6.36
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0
linux	linux_kernel	7.0

JSON

To clipboard

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          "confidentialityImpact": "NONE",
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CVE-2026-23405 (GCVE-0-2026-23405)

Vulnerability from cvelistv5 – Published: 2026-04-01 08:36 – Updated: 2026-04-18 08:58

Title

apparmor: fix: limit the number of levels of policy namespaces

Summary

Severity ?

No CVSS data available.

Assigner

Linux

References

URL

Tags

	https://git.kernel.org/stable/c/6b396cc2f0365e684…
	https://git.kernel.org/stable/c/87d0cecc900e55d55…
	https://git.kernel.org/stable/c/b1226e37eb3754d38…
	https://git.kernel.org/stable/c/3f8699b3ee0c04b4b…
	https://git.kernel.org/stable/c/853ce31ca72097d23…
	https://git.kernel.org/stable/c/d42b2b6bb77ca40ee…
	https://git.kernel.org/stable/c/7b6495ead2c611647…
	https://git.kernel.org/stable/c/306039414932c80f8…

Impacted products

Vendor

Product

Version

Linux

Affected: c88d4c7b049e87998ac0a9f455aa545cc895ef92 , < 6b396cc2f0365e684fc1d3547d18ef79fcee225d (git)
Affected: c88d4c7b049e87998ac0a9f455aa545cc895ef92 , < 87d0cecc900e55d55fc4dbfb43ac93e269c7a5b3 (git)
Affected: c88d4c7b049e87998ac0a9f455aa545cc895ef92 , < b1226e37eb3754d389721c135db6107db94c7a72 (git)
Affected: c88d4c7b049e87998ac0a9f455aa545cc895ef92 , < 3f8699b3ee0c04b4b9bc27b82cd89a40e81e1d2e (git)
Affected: c88d4c7b049e87998ac0a9f455aa545cc895ef92 , < 853ce31ca72097d23991a06876a2ccb5cb64b603 (git)
Affected: c88d4c7b049e87998ac0a9f455aa545cc895ef92 , < d42b2b6bb77ca40ee34ab74ad79305840b5f315d (git)
Affected: c88d4c7b049e87998ac0a9f455aa545cc895ef92 , < 7b6495ead2c611647f6b11441a852324e3eb8616 (git)
Affected: c88d4c7b049e87998ac0a9f455aa545cc895ef92 , < 306039414932c80f8420695a24d4fe10c84ccfb2 (git)

Linux

Affected: 2.6.36
Unaffected: 0 , < 2.6.36 (semver)
Unaffected: 5.10.253 , ≤ 5.10.* (semver)
Unaffected: 5.15.203 , ≤ 5.15.* (semver)
Unaffected: 6.1.169 , ≤ 6.1.* (semver)
Unaffected: 6.6.130 , ≤ 6.6.* (semver)
Unaffected: 6.12.77 , ≤ 6.12.* (semver)
Unaffected: 6.18.18 , ≤ 6.18.* (semver)
Unaffected: 6.19.8 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "security/apparmor/include/policy_ns.h",
            "security/apparmor/policy_ns.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
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              "status": "unaffected",
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              "status": "unaffected",
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    "datePublished": "2026-04-01T08:36:35.697Z",
    "dateReserved": "2026-01-13T15:37:46.012Z",
    "dateUpdated": "2026-04-18T08:58:39.212Z",
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}

Sightings

Author	Source	Type	Date

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.

Action not permitted

FKIE_CVE-2026-23405

CVE-2026-23405 (GCVE-0-2026-23405)

Tags

Sightings

Nomenclature