CVE-2026-23403
published 2026-04-01CVE-2026-23403: In the Linux kernel, the following vulnerability has been resolved: apparmor: fix memory leak in verify_header The function sets `*ns = NULL` on every call…
PriorityP418medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.18%
7.4th percentile
In the Linux kernel, the following vulnerability has been resolved:
apparmor: fix memory leak in verify_header
The function sets `*ns = NULL` on every call, leaking the namespace
string allocated in previous iterations when multiple profiles are
unpacked. This also breaks namespace consistency checking since *ns
is always NULL when the comparison is made.
Remove the incorrect assignment.
The caller (aa_unpack) initializes *ns to NULL once before the loop,
which is sufficient.
Affected
43 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.1.164-1 (bookworm) | linux 6.1.164-1 (bookworm) |
| linux | linux | — | — |
| linux | linux | >= dd51c84857630e77c139afe4d9bba65fc051dc3f < 9d678eb0fe55c9195d9a253e8c5b82a87b930737 | 9d678eb0fe55c9195d9a253e8c5b82a87b930737 |
| linux | linux | >= dd51c84857630e77c139afe4d9bba65fc051dc3f < 6b79abcb3c985e153fcf9d395e1d4336081aabc2 | 6b79abcb3c985e153fcf9d395e1d4336081aabc2 |
| linux | linux | >= dd51c84857630e77c139afe4d9bba65fc051dc3f < bcf82c0c5a8b383fd2d5d8f3fd880cdcab2ac557 | bcf82c0c5a8b383fd2d5d8f3fd880cdcab2ac557 |
| linux | linux | >= dd51c84857630e77c139afe4d9bba65fc051dc3f < 663ce34786e759ebcbeb3060685c20bcc886d51a | 663ce34786e759ebcbeb3060685c20bcc886d51a |
| linux | linux | >= dd51c84857630e77c139afe4d9bba65fc051dc3f < 786e2c2a87d9c505f33321d1fd23a176aa8ddeb1 | 786e2c2a87d9c505f33321d1fd23a176aa8ddeb1 |
| linux | linux | >= dd51c84857630e77c139afe4d9bba65fc051dc3f < 4f0889f2df1ab99224a5e1ac4e20437eea5fe38e | 4f0889f2df1ab99224a5e1ac4e20437eea5fe38e |
| linux | linux | >= dd51c84857630e77c139afe4d9bba65fc051dc3f < 42fd831abfc15d0643c14688f0522556b347e7e6 | 42fd831abfc15d0643c14688f0522556b347e7e6 |
| linux | linux | >= dd51c84857630e77c139afe4d9bba65fc051dc3f < e38c55d9f834e5b848bfed0f5c586aaf45acb825 | e38c55d9f834e5b848bfed0f5c586aaf45acb825 |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 0 < 5.10.251-1 | 5.10.251-1 |
| linux | linux_kernel | >= 0 < 6.1.164-1 | 6.1.164-1 |
| linux | linux_kernel | >= 0 < 6.12.74-2 | 6.12.74-2 |
| linux | linux_kernel | >= 0 < 6.19.6-2 | 6.19.6-2 |
| linux | linux_kernel | >= 3.12.1 < 5.10.253 | 5.10.253 |
| linux | linux_kernel | >= 5.11 < 5.15.203 | 5.15.203 |
| linux | linux_kernel | >= 5.16 < 6.1.169 | 6.1.169 |
| linux | linux_kernel | >= 6.13 < 6.18.18 | 6.18.18 |
| linux | linux_kernel | >= 6.19 < 6.19.8 | 6.19.8 |
| linux | linux_kernel | >= 6.2 < 6.6.130 | 6.6.130 |
| linux | linux_kernel | >= 6.7 < 6.12.77 | 6.12.77 |
| ubuntu | linux | — | — |
| ubuntu | linux-aws | — | — |
CVSS provenance
nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv7.2HIGH
vendor_ubuntu7.8HIGH
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VulDB
Linux Kernel up to 7.0-rc3 apparmor verify_header memory leak (EUVD-2026-17831 / WID-SEC-2026-0950)
vuldb·2026-04-20
CVE-2026-23403 [CRITICAL] Linux Kernel up to 7.0-rc3 apparmor verify_header memory leak (EUVD-2026-17831 / WID-SEC-2026-0950)
A vulnerability, which was classified as critical, has been found in Linux Kernel up to 6.6.129/6.12.76/6.18.17/6.19.7/7.0-rc3. This vulnerability affects the function verify_header of the component apparmor. Performing a manipulation results in memory leak.
This vulnerability is identified as CVE-2026-23403. The attack can only be performed from the local network. There is not any exploit available.
It is advisable to upgrade the affected component.
OSV
linux-oem-6.17 vulnerabilities
osv·2026-04-06·CVSS 7.2
CVE-2025-62626 [HIGH] linux-oem-6.17 vulnerabilities
linux-oem-6.17 vulnerabilities
It was discovered that some AMD Zen 5 processors supporting RDSEED
instruction did not properly handle entropy, potentially resulting in the
consumption of insufficiently random values. A local attacker could
possibly use this issue to influence the values returned by the RDSEED
instruction causing loss of confidentiality and integrity. (CVE-2025-62626)
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853, CVE-2026-23268, CVE-2026-23269, CVE-2026
OSV
CVE-2026-23403: In the Linux kernel, the following vulnerability has been resolved: apparmor: fix memory leak in verify_header The function sets `*ns = NULL` on every
osv·2026-04-01
CVE-2026-23403 CVE-2026-23403: In the Linux kernel, the following vulnerability has been resolved: apparmor: fix memory leak in verify_header The function sets `*ns = NULL` on every
In the Linux kernel, the following vulnerability has been resolved: apparmor: fix memory leak in verify_header The function sets `*ns = NULL` on every call, leaking the namespace string allocated in previous iterations when multiple profiles are unpacked. This also breaks namespace consistency checking since *ns is always NULL when the comparison is made. Remove the incorrect assignment. The caller (aa_unpack) initializes *ns to NULL once before the loop, which is sufficient.
GHSA
GHSA-rr4h-g2x9-f96p: In the Linux kernel, the following vulnerability has been resolved:
apparmor: fix memory leak in verify_header
The function sets `*ns = NULL` on eve
ghsa_unreviewed·2026-04-01
CVE-2026-23403 GHSA-rr4h-g2x9-f96p: In the Linux kernel, the following vulnerability has been resolved:
apparmor: fix memory leak in verify_header
The function sets `*ns = NULL` on eve
In the Linux kernel, the following vulnerability has been resolved:
apparmor: fix memory leak in verify_header
The function sets `*ns = NULL` on every call, leaking the namespace
string allocated in previous iterations when multiple profiles are
unpacked. This also breaks namespace consistency checking since *ns
is always NULL when the comparison is made.
Remove the incorrect assignment.
The caller (aa_unpack) initializes *ns to NULL once before the loop,
which is sufficient.
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2026-05-11·CVSS 5.5
CVE-2026-23411 [MEDIUM] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853, CVE-2026-23268, CVE-2026-23269, CVE-2026-23403,
CVE-2026-23404, CVE-2026-23405, CVE-2026-23410, CVE-2026-23411)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- GPU drivers;
- Network drivers;
Ubuntu
Linux kernel vulnerabilities
vendor_ubuntu·2026-05-11·CVSS 5.5
CVE-2026-23411 [MEDIUM] Linux kernel vulnerabilities
Title: Linux kernel vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853, CVE-2026-23268, CVE-2026-23269, CVE-2026-23403,
CVE-2026-23404, CVE-2026-23405, CVE-2026-23410, CVE-2026-23411)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- ARM64 architecture;
- Cryptogra
Ubuntu
Linux kernel (Xilinx) vulnerabilities
vendor_ubuntu·2026-05-07·CVSS 6.4
CVE-2025-68288 [MEDIUM] Linux kernel (Xilinx) vulnerabilities
Title: Linux kernel (Xilinx) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Josh Eads, Kristoffer Janke, Eduardo Vela Nava, Tavis Ormandy, and Matteo
Rizzo discovered that some AMD Zen processors did not properly verify the
signature of CPU microcode. This flaw is known as EntrySign. A privileged
attacker could possibly use this issue to cause load malicious CPU
microcode causing loss of integrity and confidentiality. (CVE-2024-36347)
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation,
Ubuntu
Linux kernel (Azure) vulnerabilities
vendor_ubuntu·2026-05-07·CVSS 7.8
CVE-2025-22058 [HIGH] Linux kernel (Azure) vulnerabilities
Title: Linux kernel (Azure) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853, CVE-2026-23268, CVE-2026-23269, CVE-2026-23403,
CVE-2026-23404, CVE-2026-23405, CVE-2026-23406, CVE-2026-23407,
CVE-2026-23408, CVE-2026-23409, CVE-2026-23410, CVE-2026-23411)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corre
Ubuntu
Linux kernel (BlueField) vulnerabilities
vendor_ubuntu·2026-04-29·CVSS 4.7
CVE-2022-48875 [MEDIUM] Linux kernel (BlueField) vulnerabilities
Title: Linux kernel (BlueField) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853, CVE-2026-23268, CVE-2026-23269, CVE-2026-23403,
CVE-2026-23404, CVE-2026-23405, CVE-2026-23406, CVE-2026-23407,
CVE-2026-23408, CVE-2026-23409, CVE-2026-23410, CVE-2026-23411)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update c
Ubuntu
Linux kernel (Azure) vulnerabilities
vendor_ubuntu·2026-04-22·CVSS 4.7
CVE-2026-23410 [MEDIUM] Linux kernel (Azure) vulnerabilities
Title: Linux kernel (Azure) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853, CVE-2026-23268, CVE-2026-23269, CVE-2026-23403,
CVE-2026-23404, CVE-2026-23405, CVE-2026-23406, CVE-2026-23407,
CVE-2026-23408, CVE-2026-23409, CVE-2026-23410, CVE-2026-23411)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corre
Ubuntu
Linux kernel (Raspberry Pi) vulnerabilities
vendor_ubuntu·2026-04-20·CVSS 4.7
CVE-2025-40215 [MEDIUM] Linux kernel (Raspberry Pi) vulnerabilities
Title: Linux kernel (Raspberry Pi) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corrects flaws in the following subsystems:
- x86 architecture;
- GPIO subsystem;
- GPU drivers;
- BTRFS file system;
- XFRM subsystem;
- IPv4 networking;
- IPv6 networking;
Ubuntu
Linux kernel (Azure) vulnerabilities
vendor_ubuntu·2026-04-13·CVSS 7.8
CVE-2024-53114 [HIGH] Linux kernel (Azure) vulnerabilities
Title: Linux kernel (Azure) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853, CVE-2026-23268, CVE-2026-23269, CVE-2026-23403,
CVE-2026-23404, CVE-2026-23405, CVE-2026-23406, CVE-2026-23407,
CVE-2026-23408, CVE-2026-23409, CVE-2026-23410, CVE-2026-23411)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update corre
Ubuntu
Linux kernel (Azure FIPS) vulnerabilities
vendor_ubuntu·2026-04-09·CVSS 7.8
CVE-2025-21833 [HIGH] Linux kernel (Azure FIPS) vulnerabilities
Title: Linux kernel (Azure FIPS) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853, CVE-2026-23268, CVE-2026-23269, CVE-2026-23403,
CVE-2026-23404, CVE-2026-23405, CVE-2026-23406, CVE-2026-23407,
CVE-2026-23408, CVE-2026-23409, CVE-2026-23410, CVE-2026-23411)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update
Ubuntu
Linux kernel (Azure FIPS) vulnerabilities
vendor_ubuntu·2026-04-09·CVSS 7.8
CVE-2025-71125 [HIGH] Linux kernel (Azure FIPS) vulnerabilities
Title: Linux kernel (Azure FIPS) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853, CVE-2026-23268, CVE-2026-23269, CVE-2026-23403,
CVE-2026-23404, CVE-2026-23405, CVE-2026-23406, CVE-2026-23407,
CVE-2026-23408, CVE-2026-23409, CVE-2026-23410, CVE-2026-23411)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
This update
Ubuntu
Linux kernel (Intel IoTG Real-time) vulnerabilities
vendor_ubuntu·2026-04-09·CVSS 7.8
CVE-2026-23410 [HIGH] Linux kernel (Intel IoTG Real-time) vulnerabilities
Title: Linux kernel (Intel IoTG Real-time) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibly escape a container.
(LP: #2143853, CVE-2026-23268, CVE-2026-23269, CVE-2026-23403,
CVE-2026-23404, CVE-2026-23405, CVE-2026-23406, CVE-2026-23407,
CVE-2026-23408, CVE-2026-23409, CVE-2026-23410, CVE-2026-23411)
Several security issues were discovered in the Linux kernel.
An attacker could possibly use these to compromise the system.
Th
Ubuntu
Linux kernel (OEM) vulnerabilities
vendor_ubuntu·2026-04-06·CVSS 7.2
CVE-2026-23404 [HIGH] Linux kernel (OEM) vulnerabilities
Title: Linux kernel (OEM) vulnerabilities
Summary: Several security issues were fixed in the Linux kernel.
It was discovered that some AMD Zen 5 processors supporting RDSEED
instruction did not properly handle entropy, potentially resulting in the
consumption of insufficiently random values. A local attacker could
possibly use this issue to influence the values returned by the RDSEED
instruction causing loss of confidentiality and integrity. (CVE-2025-62626)
Qualys discovered that several vulnerabilities existed in the AppArmor
Linux kernel Security Module (LSM). An unprivileged local attacker could
use these issues to load, replace, and remove arbitrary AppArmor profiles
causing denial of service, exposure of sensitive information (kernel
memory), local privilege escalation, or possibl
Red Hat
kernel: apparmor: fix memory leak in verify_header
vendor_redhat·2026-04-01
CVE-2026-23403 CWE-763 kernel: apparmor: fix memory leak in verify_header
kernel: apparmor: fix memory leak in verify_header
In the Linux kernel, the following vulnerability has been resolved:
apparmor: fix memory leak in verify_header
The function sets `*ns = NULL` on every call, leaking the namespace
string allocated in previous iterations when multiple profiles are
unpacked. This also breaks namespace consistency checking since *ns
is always NULL when the comparison is made.
Remove the incorrect assignment.
The caller (aa_unpack) initializes *ns to NULL once before the loop,
which is sufficient.
A flaw was found in AppArmor within the Linux kernel. This vulnerability, located in the verify_header function, causes a memory leak by incorrectly handling namespace strings when multiple security profiles are processed. This can lead to a gradual depletion of sys
Debian
CVE-2026-23403: linux - In the Linux kernel, the following vulnerability has been resolved: apparmor: f...
vendor_debian·2026
CVE-2026-23403 CVE-2026-23403: linux - In the Linux kernel, the following vulnerability has been resolved: apparmor: f...
In the Linux kernel, the following vulnerability has been resolved: apparmor: fix memory leak in verify_header The function sets `*ns = NULL` on every call, leaking the namespace string allocated in previous iterations when multiple profiles are unpacked. This also breaks namespace consistency checking since *ns is always NULL when the comparison is made. Remove the incorrect assignment. The caller (aa_unpack) initializes *ns to NULL once before the loop, which is sufficient.
Scope: local
bookworm: resolved (fixed in 6.1.164-1)
bullseye: resolved (fixed in 5.10.251-1)
forky: resolved (fixed in 6.19.6-2)
sid: resolved (fixed in 6.19.6-2)
trixie: resolved (fixed in 6.12.74-2)
No detection rules found.
No public exploits indexed.
https://git.kernel.org/stable/c/42fd831abfc15d0643c14688f0522556b347e7e6https://git.kernel.org/stable/c/4f0889f2df1ab99224a5e1ac4e20437eea5fe38ehttps://git.kernel.org/stable/c/663ce34786e759ebcbeb3060685c20bcc886d51ahttps://git.kernel.org/stable/c/6b79abcb3c985e153fcf9d395e1d4336081aabc2https://git.kernel.org/stable/c/786e2c2a87d9c505f33321d1fd23a176aa8ddeb1https://git.kernel.org/stable/c/9d678eb0fe55c9195d9a253e8c5b82a87b930737https://git.kernel.org/stable/c/bcf82c0c5a8b383fd2d5d8f3fd880cdcab2ac557https://git.kernel.org/stable/c/e38c55d9f834e5b848bfed0f5c586aaf45acb825
2026-04-01
Published