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

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 ")

Published: 2026-04-01 Last update: 2026-06-17 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Conclusion & alert: CVE-2026-23408 is rated Low Risk (34.1/100): CVSS High severity, with low exploitation likelihood (EPSS 0.18%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-23408

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.02% 0.18% +0.16%
2 2026-04-01 0.02%

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-23408

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.8 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.8 5.9 416baaa9-dc9f-4396-8d5f-8c081fb06d67
7.8 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.8 5.9 [email protected]

Weakness enumeration for CVE-2026-23408

GitHub Security Advisory for CVE-2026-23408

GHSA-qcx9-4fj7-jf29 · Severity: high — In the Linux kernel, the following vulnerability has been resolved: apparmor: Fix double free of...

OS Trackers for CVE-2026-23408

vendor priority summary link
debian not yet assigned CVE-2026-23408 not yet assigned priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2026-23408
redhat https://access.redhat.com/security/cve/CVE-2026-23408
suse medium CVE-2026-23408 severity moderate: SUSE including 40 source package names (apache2-mod_apparmor, apparmor, …), 394 product×package rows across 41 product lines (SUSE Linux Enterprise High Availability Extension 15 SP7, SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS, … (41 product lines)): Known Not Affected 394. https://www.suse.com/security/cve/CVE-2026-23408/
ubuntu medium CVE-2026-23408 medium priority: Ubuntu including 157 source packages (linux, linux-allwinner-5.19, …), 1413 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): DNE 1017, ignored 169, released 160, not-affected 56, needs-triage 6, needed 3, pending 2. https://ubuntu.com/security/CVE-2026-23408

Affected software / configurations for CVE-2026-23408

Vendor Product Version Raw CPE
linux linux_kernel >= 5.5.1, < 5.10.253 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.11, < 5.15.203 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.16, < 6.1.169 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.2, < 6.6.130 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.7, < 6.12.77 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.13, < 6.18.18 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 6.19, < 6.19.8 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel 5.5 cpe:2.3:o:linux:linux_kernel:5.5:-:*:*:*:*:*:*
linux linux_kernel 7.0 cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*
linux linux_kernel 7.0 cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*
linux linux_kernel 7.0 cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*
linux linux_kernel 7.0 cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*
linux linux_kernel 7.0 cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*
linux linux_kernel 7.0 cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*
linux linux_kernel 7.0 cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:*

References for CVE-2026-23408

cvelogic Threat Intelligence