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NVD / CVE Program· CNA Linux

CVE-2026-23408: apparmor: Fix double free of ns_name in aa_replace_profiles()

Noroxi assessment

Priority: Monitor (action score 31/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.18% (FIRST EPSS).
  • Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: Linux Linux 18b5233e860c294a847ee07869d93c0b8673a54b, 35f4caec1352054b9a61cfdf2bf1898073637aa0, 55ef2af7490aaf72f8ffe11ec44c6bcb7eb2162a; azl3 kernel 6.6.0.0-1 on Azure Linux 3.0 6.6.130.1-1; cbl2 kernel 5.15.202.1-1 on CBL-Mariner 2.0 Release Notes.

Low priority for now. Upgrade to Linux Linux 18b5233e860c294a847ee07869d93c0b8673a54b, 35f4caec1352054b9a61cfdf2bf1898073637aa0, 55ef2af7490aaf72f8ffe11ec44c6bcb7eb2162a; azl3 kernel 6.6.0.0-1 on Azure Linux 3.0 6.6.130.1-1; cbl2 kernel 5.15.202.1-1 on CBL-Mariner 2.0 Release Notes or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

In the Linux kernel, the following vulnerability has been resolved: apparmor: Fix double free of ns_name in aa_replace_profiles() if ns_name is NULL after 1071 error = aa_unpack(udata, &lh, &ns_name); and if ent->ns_name contains an ns_name in 1089 } else if (ent->ns_name) { then ns_name is assigned the ent->ns_name 1095 ns_name = ent->ns_name; however ent->ns_name is freed at 1262 aa_load_ent_free(ent); and then again when freeing ns_name at 1270 kfree(ns_name); Fix this by NULLing out ent->ns_name after it is transferred to ns_name ")

HighCVSS 7.8 · v3.1—No exploit Fix available
Published
Apr 1, 2026
Updated
Aug 5, 2026
EPSS
0.1% · 8th percentile

Report tools

JSON

Action score

31

Monitor

Low priority for now.

CVSS
31 / 40 · 7.8 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.1%

CNA vs NVD score

NVD
7.8
CNA · Linux
7.8
agree

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

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When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
linuxlinux kernel

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • linux linux kernel5.5.1 and later · before 5.10.253
  • linux linux kernel5.11 and later · before 5.15.203
  • linux linux kernel5.16 and later · before 6.1.169
  • linux linux kernel6.2 and later · before 6.6.130
  • linux linux kernel6.7 and later · before 6.12.77
  • linux linux kernel6.13 and later · before 6.18.18
  • linux linux kernel6.19 and later · before 6.19.8
  • linux linux kernel5.5
  • linux linux kernel7.0

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.

  • Linux Linux

    • 5.5affected
    • 145a0ef21c8e944957f58e2c8ffcd8a10f46266a and later · before c6347a2116ecccb8fd9ee4ebc75ae41d1d7ef689affected · git
    • 145a0ef21c8e944957f58e2c8ffcd8a10f46266a and later · before c053ae381ce227577567d1ef10090ce7506d7a28affected · git
    • 145a0ef21c8e944957f58e2c8ffcd8a10f46266a and later · before 35f4caec1352054b9a61cfdf2bf1898073637aa0affected · git
    • 145a0ef21c8e944957f58e2c8ffcd8a10f46266a and later · before 55ef2af7490aaf72f8ffe11ec44c6bcb7eb2162aaffected · git
    • 145a0ef21c8e944957f58e2c8ffcd8a10f46266a and later · before 86feeccd6b93ed94bd6655f30de80f163f8d5a45affected · git
    • 145a0ef21c8e944957f58e2c8ffcd8a10f46266a and later · before 7998ab3010d2317643f91828f1853d954ef31387affected · git
    • 145a0ef21c8e944957f58e2c8ffcd8a10f46266a and later · before 18b5233e860c294a847ee07869d93c0b8673a54baffected · git
    • 145a0ef21c8e944957f58e2c8ffcd8a10f46266a and later · before 5df0c44e8f5f619d3beb871207aded7c78414502affected · git
    • before 5.5not affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:12linuxbefore 6.1.164-16.1.164-1
Debian:13linuxbefore 6.12.74-26.12.74-2
Debian:14linuxbefore 6.19.6-26.19.6-2
SUSE:Linux Enterprise Live Patching 15 SP6kernel-defaultbefore 6.4.0-150600.23.112.16.4.0-150600.23.112.1
SUSE:Linux Enterprise Live Patching 15 SP6kernel-livepatch-SLE15-SP6_Update_26before 1-150600.13.3.11-150600.13.3.1
SUSE:Linux Enterprise Server 15 SP6-LTSSkernel-64kbbefore 6.4.0-150600.23.112.16.4.0-150600.23.112.1
SUSE:Linux Enterprise Server 15 SP6-LTSSkernel-default-basebefore 6.4.0-150600.23.112.1.150600.12.52.16.4.0-150600.23.112.1.150600.12.52.1
SUSE:Linux Enterprise Server 15 SP6-LTSSkernel-docsbefore 6.4.0-150600.23.112.16.4.0-150600.23.112.1
SUSE:Linux Enterprise Server 15 SP6-LTSSkernel-obs-buildbefore 6.4.0-150600.23.112.16.4.0-150600.23.112.1
SUSE:Linux Enterprise Server 15 SP6-LTSSkernel-sourcebefore 6.4.0-150600.23.112.16.4.0-150600.23.112.1
SUSE:Linux Enterprise Server 15 SP6-LTSSkernel-symsbefore 6.4.0-150600.23.112.16.4.0-150600.23.112.1
SUSE:Linux Enterprise Server 15 SP6-LTSSkernel-zfcpdumpbefore 6.4.0-150600.23.112.16.4.0-150600.23.112.1

Same product

linux: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV
    90Now
  • CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe KEV
    89Now
  • CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV
    85Now

Published before and after this one in the same product

  • ← EarlierCVE-2026-23406Apr 1, 2026 · apparmor: fix side-effect bug in match_char() macro usage
    31Monitor
  • ← EarlierCVE-2026-23407Apr 1, 2026 · apparmor: fix missing bounds check on DEFAULT table in verify_dfa()
    31Monitor
  • Later →CVE-2026-23409Apr 1, 2026 · apparmor: fix differential encoding verification
    22Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Linux Linux18b5233e860c294a847ee07869d93c0b8673a54bVendor (CNA)
Linux Linux35f4caec1352054b9a61cfdf2bf1898073637aa0Vendor (CNA)
Linux Linux55ef2af7490aaf72f8ffe11ec44c6bcb7eb2162aVendor (CNA)
Linux Linux5df0c44e8f5f619d3beb871207aded7c78414502Vendor (CNA)
Linux Linux7998ab3010d2317643f91828f1853d954ef31387Vendor (CNA)
Linux Linux86feeccd6b93ed94bd6655f30de80f163f8d5a45Vendor (CNA)
Linux Linuxc053ae381ce227577567d1ef10090ce7506d7a28Vendor (CNA)
Linux Linuxc6347a2116ecccb8fd9ee4ebc75ae41d1d7ef689Vendor (CNA)
azl3 kernel 6.6.0.0-1 on Azure Linux 3.06.6.130.1-1 · CBL-Mariner ReleasesMicrosoft (MSRC)
cbl2 kernel 5.15.202.1-1 on CBL-Mariner 2.0Release NotesMicrosoft (MSRC)
debian:linux6.1.164-1 · Debian:12Package registry (OSV)
suse:kernel-64kb6.4.0-150600.23.112.1 · SUSE:Linux Enterprise Server 15 SP6-LTSSPackage registry (OSV)
suse:kernel-default6.4.0-150600.23.112.1 · SUSE:Linux Enterprise Live Patching 15 SP6Package registry (OSV)
suse:kernel-default-base6.4.0-150600.23.112.1.150600.12.52.1 · SUSE:Linux Enterprise Server 15 SP6-LTSSPackage registry (OSV)
suse:kernel-docs6.4.0-150600.23.112.1 · SUSE:Linux Enterprise Server 15 SP6-LTSSPackage registry (OSV)
suse:kernel-livepatch-SLE15-SP6_Update_261-150600.13.3.1 · SUSE:Linux Enterprise Live Patching 15 SP6Package registry (OSV)
suse:kernel-obs-build6.4.0-150600.23.112.1 · SUSE:Linux Enterprise Server 15 SP6-LTSSPackage registry (OSV)
suse:kernel-source6.4.0-150600.23.112.1 · SUSE:Linux Enterprise Server 15 SP6-LTSSPackage registry (OSV)
suse:kernel-syms6.4.0-150600.23.112.1 · SUSE:Linux Enterprise Server 15 SP6-LTSSPackage registry (OSV)
suse:kernel-zfcpdump6.4.0-150600.23.112.1 · SUSE:Linux Enterprise Server 15 SP6-LTSSPackage registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2026-3160823 days apartsmb: server: avoid double-free in smb_direct_free_sendmsg after smb_direct_flush_send_list()
    39Monitor
  • CVE-2026-3160923 days apartsmb: client: avoid double-free in smbd_free_send_io() after smbd_send_batch_flush()
    39Monitor
  • CVE-2026-4301130 days apartnet/x25: Fix potential double free of skb
    39Monitor
  • CVE-2026-4341437 days apartscsi: qla2xxx: Completely fix fcport double free
    39Monitor
  • CVE-2026-5299384 days aparttipc: fix double-free in tipc_buf_append()
    39Monitor
  • CVE-2026-63888109 days apartscsi: target: iscsi: Fix CRC overread and double-free in iscsit_handle_text_cmd()
    39Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Local
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-415 · Double Free

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (7 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records