CVE-2026-74660: linux
Vulnerability summary
CVE-2026-74660 is a high (CVSS 7.8) vulnerability in linux. EPSS estimates a 0.13% chance of exploitation in the next 30 days, higher than 2% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 15 · Related 14Timeline
- 22-08-2026PublishedVulnerability first disclosed.
- 16-10-2026Last modifiedVulnerability information updated.
Description
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.
CVSS metrics
4 scores · 4 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- NVDNIST7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
0.13%
Chance of exploitation in the next 30 days
Percentile
2%
Versus all other CVEs
30-day change
0.00 pp
From 0.13% on 20-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeNo weakness data has been published for this record.
Affected systems
Ubuntu168 products
- linuxAll versions (No fix recorded) | < 5.15.0-198.208
- linux-allwinner-5.19All versions (No fix recorded)
- linux-awsAll versions (No fix recorded) | < 5.15.0-1117.124
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Debian2 products
- linux< 6.1.187-1 | < 6.12.105-1 | < 7.1.9-1
- linux-6.12< 6.12.107-1~deb12u1
Linux1 product
- linux≥ c83fa19603bdaeef17b815713dbbe3230c8a34ee, < 3bcce49d617c593c7606083bfdb464a1761fa68d | ≥ c83fa19603bdaeef17b815713dbbe3230c8a34ee, < 394d7939c6b2b9e6bea0844c89efb5913168d898 | ≥ c83fa19603bdaeef17b815713dbbe3230c8a34ee, < 2cac4294f184c9bc19ff82552c62b80498694c39 | ≥ c83fa19603bdaeef17b815713dbbe3230c8a34ee, < 9d8a94b48b393885e7f876c8ef68ed4da5012078 | ≥ c83fa19603bdaeef17b815713dbbe3230c8a34ee, < 6809379a860b9fccbb5435bf08343f6d081ac68d | ≥ c83fa19603bdaeef17b815713dbbe3230c8a34ee, < 47a119ec8a7e2d5c8c4e86fb1a56c4e696e500fb | ≥ c83fa19603bdaeef17b815713dbbe3230c8a34ee, < e2ab7e878bdbe80104c879c31fd2d82a476703b8 | ≥ c83fa19603bdaeef17b815713dbbe3230c8a34ee, < 30825970339c107bacaf7f61af90fcdb1f597ca1 | 4.12
3 vendors · 171 products