ipv6: fib6: fix NULL deref in fib6_walk_continue() on multi-batch dump
Summary
| CVE | CVE-2026-72392 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-08-15 06:22:12 UTC |
| Updated | 2026-08-19 17:21:00 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: ipv6: fib6: fix NULL deref in fib6_walk_continue() on multi-batch dump inet6_dump_fib() saves its progress in cb->args[1] as a positional index within the current hash chain. Between batches, a concurrent fib6_new_table() can insert a new table at the chain head, shifting all existing entries. The saved index then lands on a different table, causing fib6_dump_table() to set w->root to the wrong table while w->node still points into the previous one. fib6_walk_continue() dereferences w->node->parent (NULL) and panics: BUG: kernel NULL pointer dereference, address: 0000000000000008 RIP: 0010:fib6_walk_continue+0x6e/0x170 Call Trace: <TASK> fib6_dump_table.isra.0+0xc5/0x240 inet6_dump_fib+0xf6/0x420 rtnl_dumpit+0x30/0xa0 netlink_dump+0x15b/0x460 netlink_recvmsg+0x1d6/0x2a0 ____sys_recvmsg+0x17a/0x190 Fix by storing tb->tb6_id in cb->args[1] instead of a positional index. On resume, skip entries until the id matches; a concurrent head-insert can never match the saved id, so the walker always resumes on the correct table. |
Risk And Classification
EPSS: 0.002060000 probability, percentile 0.109510000 (date 2026-08-19)
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected 1b43af5480c351dbcb2eef478bafe179cbeb6e83 ee73a32dd258d4af66831ff006b771e19812b322 git | Not specified |
| CNA | Linux | Linux | affected 1b43af5480c351dbcb2eef478bafe179cbeb6e83 89f9c5fee3c64c5cabc34e65599308fd3c879cf9 git | Not specified |
| CNA | Linux | Linux | affected 1b43af5480c351dbcb2eef478bafe179cbeb6e83 cb90a774a9c6c46961a44949a246fbb61f5f934c git | Not specified |
| CNA | Linux | Linux | affected 1b43af5480c351dbcb2eef478bafe179cbeb6e83 27210d433a8c5fe6bf7278a04bbaeb49a81d0290 git | Not specified |
| CNA | Linux | Linux | affected 1b43af5480c351dbcb2eef478bafe179cbeb6e83 059efb48dd746518898faaa9b965511009b59639 git | Not specified |
| CNA | Linux | Linux | affected 1b43af5480c351dbcb2eef478bafe179cbeb6e83 d8a01d27873e04bebd357dc87859aa756e0b28b2 git | Not specified |
| CNA | Linux | Linux | affected 1b43af5480c351dbcb2eef478bafe179cbeb6e83 110ccbd28c9444866fcc84ba96a2ad64fa6e95ae git | Not specified |
| CNA | Linux | Linux | affected 1b43af5480c351dbcb2eef478bafe179cbeb6e83 9facb861dc6b9b9ea9793ef5032a9a826f7a4229 git | Not specified |
| CNA | Linux | Linux | affected 2.6.19 | Not specified |
| CNA | Linux | Linux | unaffected 2.6.19 semver | Not specified |
| CNA | Linux | Linux | unaffected 5.10.265 5.10.* semver | Not specified |
| CNA | Linux | Linux | unaffected 5.15.212 5.15.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.1.183 6.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.151 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.97 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.40 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.1.5 7.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.2 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/89f9c5fee3c64c5cabc34e65599308fd3c879cf9 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/059efb48dd746518898faaa9b965511009b59639 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/9facb861dc6b9b9ea9793ef5032a9a826f7a4229 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/d8a01d27873e04bebd357dc87859aa756e0b28b2 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/27210d433a8c5fe6bf7278a04bbaeb49a81d0290 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/cb90a774a9c6c46961a44949a246fbb61f5f934c | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/110ccbd28c9444866fcc84ba96a2ad64fa6e95ae | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/ee73a32dd258d4af66831ff006b771e19812b322 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.