{"id":"CVE-2026-53096","title":"bpf: Use RCU-safe iteration in dev_map_redirect_multi() SKB path","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Use RCU-safe iteration in dev_map_redirect_multi() SKB path\n\nThe DEVMAP_HASH branch in dev_map_redirect_multi() uses\nhlist_for_each_entry_safe() to iterate hash bu…","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 >= e624d4ed4aa8cc3c69d1359b0aaea539203ed266 < 4a3d0fe30b907ff324b1b49756f7e713d67f3645","Linux >= e624d4ed4aa8cc3c69d1359b0aaea539203ed266 < b089aa6e94d7a08e74d076a0fe274842dc9feccc","Linux >= e624d4ed4aa8cc3c69d1359b0aaea539203ed266 < 571a05ea1baaccc0dc1e0d227b2cbc978b96d392","Linux >= e624d4ed4aa8cc3c69d1359b0aaea539203ed266 < cb2c1f3cf65b855548e1b8d55a08bfbaa5a0901a","Linux >= e624d4ed4aa8cc3c69d1359b0aaea539203ed266 < d4c4bd231ebad70e6f30db429e9640bf378b2f52","Linux >= e624d4ed4aa8cc3c69d1359b0aaea539203ed266 < 7027e705062482a8cea43a1c13ede3c35653966f","Linux >= e624d4ed4aa8cc3c69d1359b0aaea539203ed266 < 8ed82f807bb09d2c8455aaa665f2c6cb17bc6a19","Linux 5.14"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-10-16T15:25:42.393146Z"},"published":"2026-06-24","updated":"2026-10-16","sourceUpdated":"2026-10-16T15:31:32.846Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-53096","references":[{"url":"https://git.kernel.org/stable/c/4a3d0fe30b907ff324b1b49756f7e713d67f3645"},{"url":"https://git.kernel.org/stable/c/b089aa6e94d7a08e74d076a0fe274842dc9feccc"},{"url":"https://git.kernel.org/stable/c/571a05ea1baaccc0dc1e0d227b2cbc978b96d392"},{"url":"https://git.kernel.org/stable/c/cb2c1f3cf65b855548e1b8d55a08bfbaa5a0901a"},{"url":"https://git.kernel.org/stable/c/d4c4bd231ebad70e6f30db429e9640bf378b2f52"},{"url":"https://git.kernel.org/stable/c/7027e705062482a8cea43a1c13ede3c35653966f"},{"url":"https://git.kernel.org/stable/c/8ed82f807bb09d2c8455aaa665f2c6cb17bc6a19"}],"tags":["cve.org"],"epss":0.00132,"epssPercentile":0.02456,"ingestedAt":"2026-10-16T17:24:46.731Z","slug":"CVE-2026-53096","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Use RCU-safe iteration in dev_map_redirect_multi() SKB path\n\nThe DEVMAP_HASH branch in dev_map_redirect_multi() uses\nhlist_for_each_entry_safe() to iterate hash buckets, but this function\nruns under RCU protection (called from xdp_do_generic_redirect_map()\nin softirq context). Concurrent writers (__dev_map_hash_update_elem,\ndev_map_hash_delete_elem) modify the list using RCU primitives\n(hlist_add_head_rcu, hlist_del_rcu).\n\nhlist_for_each_entry_safe() performs plain pointer dereferences without\nrcu_dereference(), missing the acquire barrier needed to pair with\nwriters' rcu_assign_pointer(). On weakly-ordered architectures (ARM64,\nPOWER), a reader can observe a partially-constructed node. It also\ndefeats CONFIG_PROVE_RCU lockdep validation and KCSAN data-race\ndetection.\n\nReplace with hlist_for_each_entry_rcu() using rcu_read_lock_bh_held()\nas the lockdep condition, consistent with the rcu_dereference_check()\nused in the DEVMAP (non-hash) branch of the same functions. Also fix\nthe same incorrect lockdep_is_held(&dtab->index_lock) condition in\ndev_map_enqueue_multi(), where the lock is not held either.\n\n## Affected\n\n- `Linux >= e624d4ed4aa8cc3c69d1359b0aaea539203ed266 < 4a3d0fe30b907ff324b1b49756f7e713d67f3645`\n- `Linux >= e624d4ed4aa8cc3c69d1359b0aaea539203ed266 < b089aa6e94d7a08e74d076a0fe274842dc9feccc`\n- `Linux >= e624d4ed4aa8cc3c69d1359b0aaea539203ed266 < 571a05ea1baaccc0dc1e0d227b2cbc978b96d392`\n- `Linux >= e624d4ed4aa8cc3c69d1359b0aaea539203ed266 < cb2c1f3cf65b855548e1b8d55a08bfbaa5a0901a`\n- `Linux >= e624d4ed4aa8cc3c69d1359b0aaea539203ed266 < d4c4bd231ebad70e6f30db429e9640bf378b2f52`\n- `Linux >= e624d4ed4aa8cc3c69d1359b0aaea539203ed266 < 7027e705062482a8cea43a1c13ede3c35653966f`\n- `Linux >= e624d4ed4aa8cc3c69d1359b0aaea539203ed266 < 8ed82f807bb09d2c8455aaa665f2c6cb17bc6a19`\n- `Linux 5.14`\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":[]}