{"id":"CVE-2026-31657","summary":"batman-adv: hold claim backbone gateways by reference","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nbatman-adv: hold claim backbone gateways by reference\n\nbatadv_bla_add_claim() can replace claim-\u003ebackbone_gw and drop the old\ngateway's last reference while readers still follow the pointer.\n\nThe netlink claim dump path dereferences claim-\u003ebackbone_gw-\u003eorig and\ntakes claim-\u003ebackbone_gw-\u003ecrc_lock without pinning the underlying\nbackbone gateway. batadv_bla_check_claim() still has the same naked\npointer access pattern.\n\nReuse batadv_bla_claim_get_backbone_gw() in both readers so they operate\non a stable gateway reference until the read-side work is complete.\nThis keeps the dump and claim-check paths aligned with the lifetime\nrules introduced for the other BLA claim readers.","modified":"2026-05-18T05:59:53.065622911Z","published":"2026-04-24T14:45:08.867Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31657.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/1f2dc36c297d27733f1b380ea644cf15a361bd7b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/2f55b58b5a0bbed192d60c444a45a49cdf1b545f"},{"type":"WEB","url":"https://git.kernel.org/stable/c/4dee4c0688443aaf5bbec74aa203c851d1d53c35"},{"type":"WEB","url":"https://git.kernel.org/stable/c/7962b522222628596ca9ecc8722efc95367aadbd"},{"type":"WEB","url":"https://git.kernel.org/stable/c/82d8701b2c930d0e96b0dbc9115a218d791cb0d2"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f4858832ddef2f39f21e30b7226bbcd3c4b2bc96"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31657.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-31657"},{"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":"f4858832ddef2f39f21e30b7226bbcd3c4b2bc96"},{"fixed":"2f55b58b5a0bbed192d60c444a45a49cdf1b545f"},{"fixed":"7962b522222628596ca9ecc8722efc95367aadbd"},{"fixed":"4dee4c0688443aaf5bbec74aa203c851d1d53c35"},{"fixed":"1f2dc36c297d27733f1b380ea644cf15a361bd7b"},{"fixed":"82d8701b2c930d0e96b0dbc9115a218d791cb0d2"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-31657.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.5.0"},{"fixed":"6.1.169"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.135"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.82"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.23"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"6.19.13"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-31657.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}