{"id":"CVE-2026-64452","title":"6lowpan: fix NHC entry use-after-free on error path","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\n6lowpan: fix NHC entry use-after-free on error path\n\nlowpan_nhc_do_uncompression() looks up an NHC descriptor while holding\nlowpan_nhc_lock.  If the descriptor has no u…","severity":"high","cvss":7.1,"cvssVector":"CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= 92aa7c65d295f3cbb96904afe335f683e55584b8 < 9c2f5c0829a8c8b904dae36be6d8056b719ac605","Linux >= 92aa7c65d295f3cbb96904afe335f683e55584b8 < 80b5c8779acee0550845394fb3e5176a398aa24c","Linux >= 92aa7c65d295f3cbb96904afe335f683e55584b8 < cc27aea4d454abfb385ee2c9499c78b96db9b728","Linux >= 92aa7c65d295f3cbb96904afe335f683e55584b8 < a8e3a94711134e898c6021a6b77374efa91b3639","Linux >= 92aa7c65d295f3cbb96904afe335f683e55584b8 < 593b78bb3c7ef0c6e9ae6fdf5afa80a5f7573168","Linux >= 92aa7c65d295f3cbb96904afe335f683e55584b8 < 0beccbcf50de125be5520d0ffc59af4bb8655482","Linux >= 92aa7c65d295f3cbb96904afe335f683e55584b8 < b713aa0cc344f10f7a9928a230b5f5e780d04078","Linux >= 92aa7c65d295f3cbb96904afe335f683e55584b8 < 1720db928e5a58ca7d75ac1d514c3b73fd7061a7","Linux 4.1"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-10-16T15:41:07.187657Z"},"published":"2026-07-25","updated":"2026-10-16","sourceUpdated":"2026-10-16T15:42:37.341Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-64452","references":[{"url":"https://git.kernel.org/stable/c/9c2f5c0829a8c8b904dae36be6d8056b719ac605"},{"url":"https://git.kernel.org/stable/c/80b5c8779acee0550845394fb3e5176a398aa24c"},{"url":"https://git.kernel.org/stable/c/cc27aea4d454abfb385ee2c9499c78b96db9b728"},{"url":"https://git.kernel.org/stable/c/a8e3a94711134e898c6021a6b77374efa91b3639"},{"url":"https://git.kernel.org/stable/c/593b78bb3c7ef0c6e9ae6fdf5afa80a5f7573168"},{"url":"https://git.kernel.org/stable/c/0beccbcf50de125be5520d0ffc59af4bb8655482"},{"url":"https://git.kernel.org/stable/c/b713aa0cc344f10f7a9928a230b5f5e780d04078"},{"url":"https://git.kernel.org/stable/c/1720db928e5a58ca7d75ac1d514c3b73fd7061a7"}],"tags":["cve.org"],"epss":0.00219,"epssPercentile":0.11511,"ingestedAt":"2026-10-16T17:24:46.822Z","slug":"CVE-2026-64452","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\n6lowpan: fix NHC entry use-after-free on error path\n\nlowpan_nhc_do_uncompression() looks up an NHC descriptor while holding\nlowpan_nhc_lock.  If the descriptor has no uncompress callback, the error\npath drops the lock before printing nhc->name.\n\nlowpan_nhc_del() removes descriptors under the same lock and then relies\non synchronize_net() before the owning module can be unloaded.  That only\nwaits for net RX RCU readers.  lowpan_header_decompress() is also exported\nand can be reached from callers that are not necessarily covered by the net\ncore RX critical section, for example the Bluetooth 6LoWPAN L2CAP receive\npath.\n\nThis leaves a race where one task drops lowpan_nhc_lock in the error path,\nanother task unregisters and frees the matching descriptor after\nsynchronize_net() returns, and the first task then dereferences nhc->name\nfor the warning.\n\nWith the post-unlock window widened, KASAN reports:\n\n  BUG: KASAN: slab-use-after-free in lowpan_nhc_do_uncompression+0x1f4/0x220\n  Read of size 8\n  lowpan_nhc_do_uncompression\n  lowpan_header_decompress\n\nFix this by printing the warning before dropping lowpan_nhc_lock, so the\ndescriptor name is read while unregister is still excluded.  The malformed\npacket is still rejected with -ENOTSUPP.\n\n## Affected\n\n- `Linux >= 92aa7c65d295f3cbb96904afe335f683e55584b8 < 9c2f5c0829a8c8b904dae36be6d8056b719ac605`\n- `Linux >= 92aa7c65d295f3cbb96904afe335f683e55584b8 < 80b5c8779acee0550845394fb3e5176a398aa24c`\n- `Linux >= 92aa7c65d295f3cbb96904afe335f683e55584b8 < cc27aea4d454abfb385ee2c9499c78b96db9b728`\n- `Linux >= 92aa7c65d295f3cbb96904afe335f683e55584b8 < a8e3a94711134e898c6021a6b77374efa91b3639`\n- `Linux >= 92aa7c65d295f3cbb96904afe335f683e55584b8 < 593b78bb3c7ef0c6e9ae6fdf5afa80a5f7573168`\n- `Linux >= 92aa7c65d295f3cbb96904afe335f683e55584b8 < 0beccbcf50de125be5520d0ffc59af4bb8655482`\n- `Linux >= 92aa7c65d295f3cbb96904afe335f683e55584b8 < b713aa0cc344f10f7a9928a230b5f5e780d04078`\n- `Linux >= 92aa7c65d295f3cbb96904afe335f683e55584b8 < 1720db928e5a58ca7d75ac1d514c3b73fd7061a7`\n- `Linux 4.1`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":39,"depthScoreParts":{"impact":39.1,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}