In the Linux kernel, the following vulnerability has been resolved:
apparmor: fix differential encoding verification
Differential encoding allows loops to be created if it is abused. To
prevent this the unpack should verify that a diff-encode chain
terminates.
Unfortunately the differential encode verification had two bugs.
1. it conflated states that had gone through check and already been
marked, with states that were currently being checked and marked.
This means that loops in the current chain being verified are treated
as a chain that has already been verified.
2. the order bailout on already checked states compared current chain
check iterators j,k instead of using the outer loop iterator i.
Meaning a step backwards in states in the current chain verification
was being mistaken for moving to an already verified state.
Move to a double mark scheme where already verified states get a
different mark, than the current chain being kept. This enables us
to also drop the backwards verification check that was the cause of
the second error as any already verified state is already marked.
References
Configurations
Configuration 1 (hide)
|
History
24 Apr 2026, 15:23
| Type | Values Removed | Values Added |
|---|---|---|
| CWE | CWE-835 | |
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 5.5 |
| References | () https://git.kernel.org/stable/c/0fab44285445e9012674396d5c1236a67da518e0 - Patch | |
| References | () https://git.kernel.org/stable/c/1439150cd3c411228b387ab5efca92199d2a659a - Patch | |
| References | () https://git.kernel.org/stable/c/1ff4857fac56ac5a90ee63b24db05fa5e91a45aa - Patch | |
| References | () https://git.kernel.org/stable/c/34fc60b125ed1d4eb002c76b0664bf0619492167 - Patch | |
| References | () https://git.kernel.org/stable/c/39440b137546a3aa383cfdabc605fb73811b6093 - Patch | |
| References | () https://git.kernel.org/stable/c/623a9d211bbbb031bb1cbdb38b23487648167f8a - Patch | |
| References | () https://git.kernel.org/stable/c/f90e3ecd9e1ed69f1a370f866ceed1f104f3ab4a - Patch | |
| References | () https://git.kernel.org/stable/c/ff7c73744fafe944ed9a7b2b7cf6c8d5557a3d84 - Patch | |
| CPE | cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:4.17:-:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:* |
|
| First Time |
Linux
Linux linux Kernel |
18 Apr 2026, 09:16
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
01 Apr 2026, 09:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-04-01 09:16
Updated : 2026-04-24 15:23
NVD link : CVE-2026-23409
Mitre link : CVE-2026-23409
CVE.ORG link : CVE-2026-23409
JSON object : View
Products Affected
linux
- linux_kernel
CWE
CWE-835
Loop with Unreachable Exit Condition ('Infinite Loop')