CVE-2026-23409
Estado: AnalizadaMedia (5.5)—
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.
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.
Detalles técnicos trazas, registros y código del informe original
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.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 5.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.18%
- Percentil entre todas las CVEs puntuadas: 7
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (1)
CWE
- CWE-835
Referencias
- https://git.kernel.org/stable/c/0fab44285445e9012674396d5c1236a67da518e0
- https://git.kernel.org/stable/c/1439150cd3c411228b387ab5efca92199d2a659a
- https://git.kernel.org/stable/c/1ff4857fac56ac5a90ee63b24db05fa5e91a45aa
- https://git.kernel.org/stable/c/34fc60b125ed1d4eb002c76b0664bf0619492167
- https://git.kernel.org/stable/c/39440b137546a3aa383cfdabc605fb73811b6093
- https://git.kernel.org/stable/c/623a9d211bbbb031bb1cbdb38b23487648167f8a
- https://git.kernel.org/stable/c/f90e3ecd9e1ed69f1a370f866ceed1f104f3ab4a
- https://git.kernel.org/stable/c/ff7c73744fafe944ed9a7b2b7cf6c8d5557a3d84
JSON original (NVD)
Mostrar
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