{"id":"CVE-2026-89948","summary":"batman-adv: bla: fix freeing of claims on meshif deletion","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nbatman-adv: bla: fix freeing of claims on meshif deletion\n\nWhen the mesh interface is getting deleted, then\nbatadv_bla_del_backbone_claims() (via batadv_bla_purge_backbone_gw()) could\nmake sure that all claims gets removed. But this function is only executed\nwhen bat_priv-\u003ebla.claim_hash is not NULL. And since batadv_bla_free() is\nalways setting it to NULL before it is (indirectly) called, it was never\nactually executed.\n\nBut the batadv_bla_purge_claims() -\u003e batadv_handle_unclaim() is at the\nmoment too fragile because the BLA code is not handling the rehashing in\nbatadv_bla_update_orig_address(). The stored backbone address doesn't have\nto be the one actually used for the hash bucket selection during the\ninitial adding of the backbone. The batadv_handle_unclaim() can therefore\nfail to find the respective backbone for the unclaim and then stop the\ndeletion.\n\nBut the actual backbone_gw object is not needed for the unclaim because all\nrelevant information is always provided by the caller. And the check for\nthe existence of the backbone_gw doesn't provide any additional security\ncheck for the deletion of a claim.","modified":"2026-09-18T03:48:34.192413486Z","published":"2026-09-16T10:32:34.089Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89948.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/76aedcde5a2489cc971d4d1e396e784a49565e96"},{"type":"WEB","url":"https://git.kernel.org/stable/c/844a95a734f178d56c7acce14c5cce2cecff7e1a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/871acdf97f64cee8398f72b88b89e8b4f4816dbe"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8d128c932bced74e3b1625ba3d7c78ef122a88a7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9a0c47023d3254048a1588534755d4476bcc3abc"},{"type":"WEB","url":"https://git.kernel.org/stable/c/aacffa780a37e06cd5a13d33740a6e96c3a67e6c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/baeb1a28fd8e2f68193650d3664a8cd1adfd85c6"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f50edb69082a8ba990cc23d642089829f99afe6a"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89948.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89948"},{"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":"23721387c409087fd3b97e274f34d3ddc0970b74"},{"fixed":"844a95a734f178d56c7acce14c5cce2cecff7e1a"},{"fixed":"baeb1a28fd8e2f68193650d3664a8cd1adfd85c6"},{"fixed":"aacffa780a37e06cd5a13d33740a6e96c3a67e6c"},{"fixed":"76aedcde5a2489cc971d4d1e396e784a49565e96"},{"fixed":"f50edb69082a8ba990cc23d642089829f99afe6a"},{"fixed":"871acdf97f64cee8398f72b88b89e8b4f4816dbe"},{"fixed":"9a0c47023d3254048a1588534755d4476bcc3abc"},{"fixed":"8d128c932bced74e3b1625ba3d7c78ef122a88a7"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-89948.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.5.0"},{"fixed":"5.10.270"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.221"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.188"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.157"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.110"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.51"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.5"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-89948.json"}}],"schema_version":"1.9.0"}