CVE-2026-97598 | BDVDB-2026-379347 Detail
LinuxLinux
Description#
In the Linux kernel, the following vulnerability has been resolved: ipv4: fib: bound automatic table ID allocation fib_empty_table() probes every table ID from 1 until it finds a free one. IPv4 tables are stored in a 256-bucket hash table, so a dense set of IDs makes each probe walk a growing hash chain while RTNL is held. Automatic table assignment ("ip rule ... table 0") is an IPv4-only legacy path. Bound the automatically allocated ID to 4096 so the RTNL hold stays bounded, without changing lookups of explicitly specified table IDs. This changes user-visible behavior. A table-0 rule previously received the lowest free ID in 1..RT_TABLE_MAX (0xFFFFFFFF). After this patch the search stops at 4096 and the rule add fails with ENOBUFS if that range is fully occupied. Explicit table IDs above 4096 remain usable. The automatic path is unused in practice: it is IPv4-only, not documented by ip-rule, uncovered by kernel selftests, and both NetworkManager and systemd refuse table 0.
Impact#
No impact statement in the source data.
Weaknesses#
No weakness recorded in the source data.
References#
- https://git.kernel.org/stable/c/999bc00588cb305ab25065e8a8ac31da7465301c
- https://git.kernel.org/stable/c/f1f2da33eaab54b4d5cdea6d70befb2e2fb49cb6
- https://git.kernel.org/stable/c/125890702ef4417cd0ffac2e448c0cd4fbf0ac45
- https://git.kernel.org/stable/c/3080f9e653d8c057d5652db5ced8137f81b3fcbd
- https://git.kernel.org/stable/c/bc8d01d856db106f284b19961af6112e10c3e3b4
- https://git.kernel.org/stable/c/fe9a906d2bff2d2707bafd6353b5e032a42aeb35
- https://git.kernel.org/stable/c/2c29c053a6627dc4f12fcfe6b4860bcd9e5d7503
- https://git.kernel.org/stable/c/efdfb1e27a3328085b79540dfe781d537b576ea1
Exploit#
No public exploit known
History#
- Version 1Record published in the CVE List.
- Version 2Most recent update recorded in the CVE List.