{"id":"CVE-2026-64452","summary":"6lowpan: fix NHC entry use-after-free on error path","details":"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 uncompress callback, the error\npath drops the lock before printing nhc-\u003ename.\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-\u003ename\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.","modified":"2026-07-27T04:03:20.030105785Z","published":"2026-07-25T08:51:21.754Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64452.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/0beccbcf50de125be5520d0ffc59af4bb8655482"},{"type":"WEB","url":"https://git.kernel.org/stable/c/1720db928e5a58ca7d75ac1d514c3b73fd7061a7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/593b78bb3c7ef0c6e9ae6fdf5afa80a5f7573168"},{"type":"WEB","url":"https://git.kernel.org/stable/c/80b5c8779acee0550845394fb3e5176a398aa24c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9c2f5c0829a8c8b904dae36be6d8056b719ac605"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a8e3a94711134e898c6021a6b77374efa91b3639"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b713aa0cc344f10f7a9928a230b5f5e780d04078"},{"type":"WEB","url":"https://git.kernel.org/stable/c/cc27aea4d454abfb385ee2c9499c78b96db9b728"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64452.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64452"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"92aa7c65d295f3cbb96904afe335f683e55584b8"},{"fixed":"9c2f5c0829a8c8b904dae36be6d8056b719ac605"},{"fixed":"80b5c8779acee0550845394fb3e5176a398aa24c"},{"fixed":"cc27aea4d454abfb385ee2c9499c78b96db9b728"},{"fixed":"a8e3a94711134e898c6021a6b77374efa91b3639"},{"fixed":"593b78bb3c7ef0c6e9ae6fdf5afa80a5f7573168"},{"fixed":"0beccbcf50de125be5520d0ffc59af4bb8655482"},{"fixed":"b713aa0cc344f10f7a9928a230b5f5e780d04078"},{"fixed":"1720db928e5a58ca7d75ac1d514c3b73fd7061a7"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64452.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.1.0"},{"fixed":"5.10.261"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.212"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.178"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.145"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.96"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.39"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.4"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64452.json"}}],"schema_version":"1.7.5"}