{"id":"CVE-2026-74479","title":"net: pktgen: fix proc entry use-after-free","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: pktgen: fix proc entry use-after-free\n\npktgen_change_name() replaces pkt_dev->entry while holding t->if_lock.\npktgen_remove_device() removes the same entry before\n…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= 39df232f1a9ba48d41c68ee7d4046756e709cf91 < 82ed3db9269cb61e3c15bad2f6e221efce90e1e0","Linux >= 39df232f1a9ba48d41c68ee7d4046756e709cf91 < d1cc9797cf8f7aeb87e7ad01b748c6a960a819e4","Linux >= 39df232f1a9ba48d41c68ee7d4046756e709cf91 < 7991c7cff8b8622cddb3d8dee07dbe74aa4cbec4","Linux >= 39df232f1a9ba48d41c68ee7d4046756e709cf91 < 577443530cb592d5782a1f79847411a9363a65c8","Linux >= 39df232f1a9ba48d41c68ee7d4046756e709cf91 < f85a58340b91f225de3299dfa782c6414098077c","Linux >= 39df232f1a9ba48d41c68ee7d4046756e709cf91 < 4ef801b838d85c0ea5852c50667f7344ce3b6cd0","Linux >= 39df232f1a9ba48d41c68ee7d4046756e709cf91 < b006a5404470bd3eb2aa0425fc447183032047ef","Linux >= 39df232f1a9ba48d41c68ee7d4046756e709cf91 < 817ff6efdb7f484ea547218e11e17d8e43daa3b4","Linux 2.6.22"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-10-16T18:57:37.706862Z"},"published":"2026-08-15","updated":"2026-10-16","sourceUpdated":"2026-10-16T19:05:48.651Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-74479","references":[{"url":"https://git.kernel.org/stable/c/82ed3db9269cb61e3c15bad2f6e221efce90e1e0"},{"url":"https://git.kernel.org/stable/c/d1cc9797cf8f7aeb87e7ad01b748c6a960a819e4"},{"url":"https://git.kernel.org/stable/c/7991c7cff8b8622cddb3d8dee07dbe74aa4cbec4"},{"url":"https://git.kernel.org/stable/c/577443530cb592d5782a1f79847411a9363a65c8"},{"url":"https://git.kernel.org/stable/c/f85a58340b91f225de3299dfa782c6414098077c"},{"url":"https://git.kernel.org/stable/c/4ef801b838d85c0ea5852c50667f7344ce3b6cd0"},{"url":"https://git.kernel.org/stable/c/b006a5404470bd3eb2aa0425fc447183032047ef"},{"url":"https://git.kernel.org/stable/c/817ff6efdb7f484ea547218e11e17d8e43daa3b4"}],"tags":["cve.org"],"epss":0.00126,"epssPercentile":0.02031,"ingestedAt":"2026-10-16T19:46:24.355Z","slug":"CVE-2026-74479","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnet: pktgen: fix proc entry use-after-free\n\npktgen_change_name() replaces pkt_dev->entry while holding t->if_lock.\npktgen_remove_device() removes the same entry before\n_rem_dev_from_if_list() takes that lock.\n\nThis allows the following interleaving:\n\n  CPU 0 (NETDEV_CHANGENAME)       CPU 1 (kpktgend)\n  if_lock(t)\n  proc_remove(pkt_dev->entry)\n                                  proc_remove(pkt_dev->entry)\n  pkt_dev->entry = proc_create_data(...)\n  if_unlock(t)\n\nThe kthread can pass the stale proc_dir_entry to proc_remove() after the\nrename path has freed it. A reproducer with a widened race window reports:\n\n  BUG: KASAN: slab-use-after-free in proc_remove+0x78/0x80\n  Read of size 8 at addr ffff8881478fea70 by task kpktgend_0/67\n  Call Trace:\n   proc_remove+0x78/0x80\n   pktgen_remove_device.isra.0+0x11c/0x4c0\n   pktgen_thread_worker+0x1214/0x6bc0\n   kthread+0x2c6/0x3b0\n  Allocated by task 95:\n   __proc_create+0x204/0x790\n   proc_create_data+0x72/0xe0\n   pktgen_thread_write+0xd61/0x1510\n  Freed by task 28:\n   kmem_cache_free+0xcb/0x3d0\n   proc_free_inode+0x5b/0x80\n   rcu_core+0x50a/0x1850\n  The buggy address belongs to the object at ffff8881478fea00\n   which belongs to the cache proc_dir_entry of size 192\n\nMove proc_remove() into the if_lock-protected list removal helper. Keep it\nbefore list_del_rcu() to preserve the ordering required by add_device().\nThe rename path must then finish replacing the entry before removal, or\nit observes that the device is no longer on the list.\n\n## Affected\n\n- `Linux >= 39df232f1a9ba48d41c68ee7d4046756e709cf91 < 82ed3db9269cb61e3c15bad2f6e221efce90e1e0`\n- `Linux >= 39df232f1a9ba48d41c68ee7d4046756e709cf91 < d1cc9797cf8f7aeb87e7ad01b748c6a960a819e4`\n- `Linux >= 39df232f1a9ba48d41c68ee7d4046756e709cf91 < 7991c7cff8b8622cddb3d8dee07dbe74aa4cbec4`\n- `Linux >= 39df232f1a9ba48d41c68ee7d4046756e709cf91 < 577443530cb592d5782a1f79847411a9363a65c8`\n- `Linux >= 39df232f1a9ba48d41c68ee7d4046756e709cf91 < f85a58340b91f225de3299dfa782c6414098077c`\n- `Linux >= 39df232f1a9ba48d41c68ee7d4046756e709cf91 < 4ef801b838d85c0ea5852c50667f7344ce3b6cd0`\n- `Linux >= 39df232f1a9ba48d41c68ee7d4046756e709cf91 < b006a5404470bd3eb2aa0425fc447183032047ef`\n- `Linux >= 39df232f1a9ba48d41c68ee7d4046756e709cf91 < 817ff6efdb7f484ea547218e11e17d8e43daa3b4`\n- `Linux 2.6.22`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}