Answer in brief
CVE-2026-74660 records a Unknown severity vulnerability in netfilter: ebt_nflog: pin the NFLOG backend. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=c83fa19603bdaeef17b815713dbbe3230c8a34ee <3bcce49d617c593c7606083bfdb464a1761fa68d || >=c83fa19603bdaeef17b815713dbbe3230c8a34ee <394d7939c6b2b9e6bea0844c89efb5913168d898 || >=c83fa19603bdaeef17b815713dbbe3230c8a34ee <2cac4294f184c9bc19ff82552c62b80498694c39 || >=c83fa19603bdaeef17b815713dbbe3230c8a34ee <9d8a94b48b393885e7f876c8ef68ed4da5012078 || >=c83fa19603bdaeef17b815713dbbe3230c8a34ee <6809379a860b9fccbb5435bf08343f6d081ac68d || >=c83fa19603bdaeef17b815713dbbe3230c8a34ee <47a119ec8a7e2d5c8c4e86fb1a56c4e696e500fb || >=c83fa19603bdaeef17b815713dbbe3230c8a34ee <e2ab7e878bdbe80104c879c31fd2d82a476703b8 || >=c83fa19603bdaeef17b815713dbbe3230c8a34ee <30825970339c107bacaf7f61af90fcdb1f597ca1 | 3bcce49d617c593c7606083bfdb464a1761fa68d, 394d7939c6b2b9e6bea0844c89efb5913168d898, 2cac4294f184c9bc19ff82552c62b80498694c39, 9d8a94b48b393885e7f876c8ef68ed4da5012078, 6809379a860b9fccbb5435bf08343f6d081ac68d, 47a119ec8a7e2d5c8c4e86fb1a56c4e696e500fb, e2ab7e878bdbe80104c879c31fd2d82a476703b8, 30825970339c107bacaf7f61af90fcdb1f597ca1 |
| Linux/Linuxgeneric | 4.12 | Not reported |
Published upstream
Aug 22, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 22, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 22, 2026
In the Linux kernel, the following vulnerability has been resolved: netfilter: ebt_nflog: pin the NFLOG backend nf_log_unregister() runs after the per-net teardown so its final RCU grace period also drains readers that obtained the logger from a per-net binding. However, ebt_nflog passes an explicit ULOG log type to nf_log_packet() without holding a reference on the selected logger module, unlike the xt_NFLOG and nft_log frontends. An ebtables nflog rule can therefore remain callable while nfnetlink_log is unloaded. The resulting interleaving is: CPU 0 CPU 1 nfnetlink_log_fini() unregister_pernet_subsys() kfree(nfnl_log_pernet(net)) ebt_nflog_tg() nf_log_packet() nfulnl_log_packet() instance_lookup_get_rcu() The global ULOG logger is still registered at this point, so CPU 1 dereferences the per-net state after CPU 0 has freed it. KASAN reported: BUG: KASAN: slab-use-after-free in instance_lookup_get_rcu Read of size 8 at addr ff110001052e6210 by task poc/92 Call Trace: instance_lookup_get_rcu+0x1ce/0x1f0 [nfnetlink_log] nfulnl_log_packet+0x248/0x2fb0 [nfnetlink_log] nf_log_packet+0x204/0x300 ebt_nflog_tg+0x351/0x550 ebt_do_table+0xedf/0x22b0 Allocated by task 90: __kmalloc_noprof+0x186/0x470 ops_init+0x6d/0x420 register_pernet_operations+0x2f6/0x670 register_pernet_subsys+0x23/0x40 Freed by task 93: kfree+0x131/0x3c0 ops_undo_list+0x3e3/0x700 unregister_pernet_operations+0x232/0x490 unregister_pernet_subsys+0x1c/0x30 nfnetlink_log_fini+0x34/0x450 [nfnetlink_log] Acquire the ULOG logger module reference when an ebt_nflog rule is validated and release it when the rule is destroyed. Request the NFLOG backend for legacy callers when needed, matching xt_NFLOG. This prevents module teardown until all ebt_nflog rules have stopped using the logger.
Quoted source text, attributed separately from HOL analysis.