netfilter: nft_set_rbtree: fix null deref on element insertion

Summary

In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_set_rbtree: fix null deref on element insertion There is no guarantee that rb_prev() will not return NULL in nft_rbtree_gc_elem(): general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f] nft_add_set_elem+0x14b0/0x2990 nf_tables_newsetelem+0x528/0xb30 Furthermore, there is a possible use-after-free while iterating, 'node' can be free'd so we need to cache the next value to use.

Timeline

1. Oct 4, 2025, 3:17 PM UTCCVE published
2. Oct 15, 2026, 9:35 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: no · Technical impact: total

3. Oct 15, 2026, 9:41 PM UTCRecord last updated

Affected versions

• Linux Linux

  From 7ab87a326f20c52ff4d9972052d085be951c704b · fixed in b76db53ee8802ee5683f8cb401d7e2ec6f9b3d56; From 181859bdfb9734aca449512fccaee4cacce64aed · fixed in 899aa5638568abf5d69de7a7bb95e4615157375b; From 4aacf3d78424293e318c616016865380b37b9cc5 · fixed in 3fa13203b6d90cc3a33af47b058739f92ab82eef; From 2bf1435fa19d2c58054391b3bba40d5510a5758c · fixed in ec5caa765f7f6960011c919c9aeb1467940421f6; From 318cb24a4c3fce8140afaf84e4d45fcb76fb280b · fixed in a836be60a3aabcedcd9c79f545d409ace1f20ba6; From c9e6978e2725a7d4b6cd23b2facd3f11422c0643 · fixed in a337706c1fb35aac3f26b48aca80421bdbe1d33a; From c9e6978e2725a7d4b6cd23b2facd3f11422c0643 · fixed in 61ae320a29b0540c16931816299eb86bf2b66c08; From 5.10.166 · fixed in 5.10.181; From 5.15.91 · fixed in 5.15.113; From 6.1.9 · fixed in 6.1.30

• Linux Linux

  6.2

• KernelLinux

  fixed in 5.10.181; From 5.11.0 · fixed in 5.15.113; From 5.16.0 · fixed in 6.1.30; From 6.2.0 · fixed in 6.3.4

References 7