{"id":"CVE-2026-43011","title":"net/x25: Fix potential double free of skb","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/x25: Fix potential double free of skb\n\nWhen alloc_skb fails in x25_queue_rx_frame it calls kfree_skb(skb) at\nline 48 and returns 1 (error).\nThis error propagates ba…","severity":"critical","cvss":9.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 5d0aa038a90b30c9bedde0c41c1fdcd98ecb16e9","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 3f5e3005984645bf5bd129c6b13149879580b1fb","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < f782dd382203b2a8c4552a628431b7de65a19a7b","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 143d4fa68ae9efb83b0c55b12cc7f0d03732a2b1","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 524371398d8463ea7e101fce2cbf3915645d1730","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < fa1dbc93530b34fab0da9862426fe9c918c74dc0","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < c87dd137c0dad07cc55f98181ff380b0c23d2878","Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < d10a26aa4d072320530e6968ef945c8c575edf61","Linux 2.6.12"],"published":"2026-05-01","updated":"2026-09-08","sourceUpdated":"2026-09-08T08:48:21.398Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-43011","references":[{"url":"https://git.kernel.org/stable/c/5d0aa038a90b30c9bedde0c41c1fdcd98ecb16e9"},{"url":"https://git.kernel.org/stable/c/3f5e3005984645bf5bd129c6b13149879580b1fb"},{"url":"https://git.kernel.org/stable/c/f782dd382203b2a8c4552a628431b7de65a19a7b"},{"url":"https://git.kernel.org/stable/c/143d4fa68ae9efb83b0c55b12cc7f0d03732a2b1"},{"url":"https://git.kernel.org/stable/c/524371398d8463ea7e101fce2cbf3915645d1730"},{"url":"https://git.kernel.org/stable/c/fa1dbc93530b34fab0da9862426fe9c918c74dc0"},{"url":"https://git.kernel.org/stable/c/c87dd137c0dad07cc55f98181ff380b0c23d2878"},{"url":"https://git.kernel.org/stable/c/d10a26aa4d072320530e6968ef945c8c575edf61"}],"tags":["cve.org"],"epss":0.00868,"epssPercentile":0.56961,"ingestedAt":"2026-09-08T15:33:26.989Z","slug":"CVE-2026-43011","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnet/x25: Fix potential double free of skb\n\nWhen alloc_skb fails in x25_queue_rx_frame it calls kfree_skb(skb) at\nline 48 and returns 1 (error).\nThis error propagates back through the call chain:\n\nx25_queue_rx_frame returns 1\n    |\n    v\nx25_state3_machine receives the return value 1 and takes the else\nbranch at line 278, setting queued=0 and returning 0\n    |\n    v\nx25_process_rx_frame returns queued=0\n    |\n    v\nx25_backlog_rcv at line 452 sees queued=0 and calls kfree_skb(skb)\nagain\n\nThis would free the same skb twice. Looking at x25_backlog_rcv:\n\nnet/x25/x25_in.c:x25_backlog_rcv() {\n    ...\n    queued = x25_process_rx_frame(sk, skb);\n    ...\n    if (!queued)\n        kfree_skb(skb);\n}\n\n## Affected\n\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 5d0aa038a90b30c9bedde0c41c1fdcd98ecb16e9`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 3f5e3005984645bf5bd129c6b13149879580b1fb`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < f782dd382203b2a8c4552a628431b7de65a19a7b`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 143d4fa68ae9efb83b0c55b12cc7f0d03732a2b1`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 524371398d8463ea7e101fce2cbf3915645d1730`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < fa1dbc93530b34fab0da9862426fe9c918c74dc0`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < c87dd137c0dad07cc55f98181ff380b0c23d2878`\n- `Linux >= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < d10a26aa4d072320530e6968ef945c8c575edf61`\n- `Linux 2.6.12`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"midnight","depthScore":54,"depthScoreParts":{"impact":53.9,"likelihood":0.2,"exploitation":0,"ransomware":0},"changes":[]}