CVE-2025-21826: linux kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: reject mismatching sum of field_len with set key length The field length description provides the length of each separated key field in the concatenation, each field gets rounded up to 32-bits to calculate the pipapo rule width from pipapo_init(). The set key length provides the total size of the key aligned to 32-bits. Register-based arithmetics still allows for combining mismatching set key length and field length description, eg. set key length 10 and field description [ 5, 4 ] leading to pipapo width of 12.
CVE-2025-21826CVSS 5.5Linux

CVE-2025-21826: linux kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: reject mismatching sum of field_len with set key length The field length description provides the length of each separated key field in the concatenation, each field gets rounded up to 32-bits to calculate the pipapo rule width from pipapo_init(). The set key length provides the total size of the key aligned to 32-bits. Register-based arithmetics still allows for combining mismatching set key length and field length description, eg. set key length 10 and field description [ 5, 4 ] leading to pipapo width of 12.

CVSS
5.5 MEDIUM
EPSS
7.31%
Known exploited
not in KEV
Product
linux kernel

What is known

In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: reject mismatching sum of field_len with set key length The field length description provides the length of each separated key field in the concatenation, each field gets rounded up to 32-bits to calculate the pipapo rule width from pipapo_init(). The set key length provides the total size of the key aligned to 32-bits. Register-based arithmetics still allows for combining mismatching set key length and field length description, eg. set key length 10 and field description [ 5, 4 ] leading to pipapo width of 12.

Sources

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