{"id":"CVE-2026-68337","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Reject redirect helpers without a bpf_net_context\n\nThe bpf_redirect*() helpers and skb_do_redirect() obtain the per-task\nbpf_redirect_info via bpf_net_ctx_get_ri()…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Reject redirect helpers without a bpf_net_context\n\nThe bpf_redirect*() helpers and skb_do_redirect() obtain the per-task\nbpf_redirect_info via bpf_net_ctx_get_ri()…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= 3625750f05ecce21a0fce429c1ff85acfffb461b < 0f2118b757509332bb0e65f90e5233766f14bb88","Linux >= 3625750f05ecce21a0fce429c1ff85acfffb461b < aafb093adffad91d4d071e8a7e0dcd9b1d91c94a","Linux >= 3625750f05ecce21a0fce429c1ff85acfffb461b < cabfacbd5af09d3ae898ca224c4a1459e9bba15d","Linux >= 3625750f05ecce21a0fce429c1ff85acfffb461b < 3f4920d165b29052255527d8ae7619e7ec132ece","Linux 5.9"],"published":"2026-08-10","updated":"2026-09-21","sourceUpdated":"2026-09-21T14:17:16.860","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-68337","references":[{"url":"https://git.kernel.org/stable/c/0f2118b757509332bb0e65f90e5233766f14bb88","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/3f4920d165b29052255527d8ae7619e7ec132ece","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/aafb093adffad91d4d071e8a7e0dcd9b1d91c94a","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/cabfacbd5af09d3ae898ca224c4a1459e9bba15d","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd","cve.org"],"epss":0.00155,"epssPercentile":0.05062,"ingestedAt":"2026-09-21T13:37:22.846Z","slug":"CVE-2026-68337","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Reject redirect helpers without a bpf_net_context\n\nThe bpf_redirect*() helpers and skb_do_redirect() obtain the per-task\nbpf_redirect_info via bpf_net_ctx_get_ri(), which dereferences the\ncurrent->bpf_net_context unconditionally. That context is established\non the paths that run tc BPF such as sch_handle_{ingress,egress}(),\n*except* for the case where {cls,act}_bpf was attached to a proper\nqdisc. A program running from there reaches the NULL deref in two ways:\n\n* It calls bpf_redirect() directly, which dereferences the context at\n  the top of the helper:\n\n     tc qdisc add dev eth0 root handle 1: red limit 1MB min 10KB max 20KB \\\n        avpkt 1000 burst 100 qevent early_drop block 10\n     tc filter add block 10 pref 1 bpf obj redirect.o\n\n* It simply returns TC_ACT_REDIRECT without helper call: tcf_qevent_handle()\n  then dispatches to skb_do_redirect(), which dereferences the context\n\nRather than extending bpf_net_context management into the qdisc path,\nmake the redirect helpers refuse to operate when no context exists, and\nhave tcf_qevent_handle() drop a TC_ACT_REDIRECT verdict instead of\ncalling skb_do_redirect(). Previous behaviour was a crash, so nothing\nregresses by not supporting it.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}