{"id":"CVE-2026-52916","summary":"batman-adv: frag: disallow unicast fragment in fragment","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nbatman-adv: frag: disallow unicast fragment in fragment\n\nbatadv_frag_skb_buffer() is called by batadv_batman_skb_recv() when a\nBATADV_UNICAST_FRAG packet is received. Once all fragments are collected\nand the packet is reassembled, batadv_recv_frag_packet() calls\nbatadv_batman_skb_recv() again to process the defragmented payload.\n\nA malicious sender can craft a BATADV_UNICAST_FRAG packet whose reassembled\npayload is itself a BATADV_UNICAST_FRAG packet (matryoshka-style nesting).\nEach nesting level recurses through batadv_batman_skb_recv() without bound,\ngrowing the kernel stack until it is exhausted.\n\nSince refragmentation or fragments in fragments are not actually allowed,\ndiscard all packets which are still BATADV_UNICAST_FRAG packets after the\ndefragmentation process.","modified":"2026-07-10T03:54:01.149359156Z","published":"2026-06-24T07:14:13.221Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/52xxx/CVE-2026-52916.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/0c208fa3859e3a33a1c38bebc41d021166e94ac8"},{"type":"WEB","url":"https://git.kernel.org/stable/c/5418be6c2e117bf8a316582795a8e3ff90f45e5d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/5895ad21c7059a652da83fb817510f7a1e962abf"},{"type":"WEB","url":"https://git.kernel.org/stable/c/7138c35c9ad39a2fca6264af6b87466471f04ffc"},{"type":"WEB","url":"https://git.kernel.org/stable/c/aea54d0bbe156d5ab7d00d68f66149ff41f4612a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b54e459cf86943583c1aa2ee3081874e7ab1f5f3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/bc62216dc8e221e3781afa14430f45208bfa9af9"},{"type":"WEB","url":"https://git.kernel.org/stable/c/bcda4814dc6524283c0b958882cb963d75fe411d"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/52xxx/CVE-2026-52916.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-52916"},{"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":"610bfc6bc99bc83680d190ebc69359a05fc7f605"},{"fixed":"0c208fa3859e3a33a1c38bebc41d021166e94ac8"},{"fixed":"bcda4814dc6524283c0b958882cb963d75fe411d"},{"fixed":"aea54d0bbe156d5ab7d00d68f66149ff41f4612a"},{"fixed":"b54e459cf86943583c1aa2ee3081874e7ab1f5f3"},{"fixed":"5418be6c2e117bf8a316582795a8e3ff90f45e5d"},{"fixed":"5895ad21c7059a652da83fb817510f7a1e962abf"},{"fixed":"7138c35c9ad39a2fca6264af6b87466471f04ffc"},{"fixed":"bc62216dc8e221e3781afa14430f45208bfa9af9"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-52916.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.13.0"},{"fixed":"5.10.258"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.209"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.175"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.142"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.92"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.34"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.0.11"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-52916.json"}}],"schema_version":"1.7.5"}