{"api_version":"1","generated_at":"2026-07-23T15:00:30+00:00","cve":"CVE-2026-31657","urls":{"html":"https://cve.report/CVE-2026-31657","api":"https://cve.report/api/cve/CVE-2026-31657.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-31657","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-31657"},"summary":{"title":"batman-adv: hold claim backbone gateways by reference","description":"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->backbone_gw and drop the old\ngateway's last reference while readers still follow the pointer.\n\nThe netlink claim dump path dereferences claim->backbone_gw->orig and\ntakes claim->backbone_gw->crc_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.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-04-24 15:16:45","updated_at":"2026-06-01 17:16:54"},"problem_types":["CWE-476"],"metrics":[{"version":"3.1","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","score":"9.8","severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","baseScore":9.8,"baseSeverity":"CRITICAL","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"9.8","severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","data":{"baseScore":9.8,"baseSeverity":"CRITICAL","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","version":"3.1"}}],"references":[{"url":"https://git.kernel.org/stable/c/5202f071b367ffbc8e279fc7a00db14f5e587f52","name":"https://git.kernel.org/stable/c/5202f071b367ffbc8e279fc7a00db14f5e587f52","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/4dee4c0688443aaf5bbec74aa203c851d1d53c35","name":"https://git.kernel.org/stable/c/4dee4c0688443aaf5bbec74aa203c851d1d53c35","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/82d8701b2c930d0e96b0dbc9115a218d791cb0d2","name":"https://git.kernel.org/stable/c/82d8701b2c930d0e96b0dbc9115a218d791cb0d2","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/1f2dc36c297d27733f1b380ea644cf15a361bd7b","name":"https://git.kernel.org/stable/c/1f2dc36c297d27733f1b380ea644cf15a361bd7b","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/69d1ce9c72eca91203ffdb8d08bacd511100aec6","name":"https://git.kernel.org/stable/c/69d1ce9c72eca91203ffdb8d08bacd511100aec6","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/2f55b58b5a0bbed192d60c444a45a49cdf1b545f","name":"https://git.kernel.org/stable/c/2f55b58b5a0bbed192d60c444a45a49cdf1b545f","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/7962b522222628596ca9ecc8722efc95367aadbd","name":"https://git.kernel.org/stable/c/7962b522222628596ca9ecc8722efc95367aadbd","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/f4858832ddef2f39f21e30b7226bbcd3c4b2bc96","name":"https://git.kernel.org/stable/c/f4858832ddef2f39f21e30b7226bbcd3c4b2bc96","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-31657","name":"CVE 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hold claim backbone gateways by reference","CVE":"CVE-2026-31657","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"31657","Ordinal":"1","NoteData":"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->backbone_gw and drop the old\ngateway's last reference while readers still follow the pointer.\n\nThe netlink claim dump path dereferences claim->backbone_gw->orig and\ntakes claim->backbone_gw->crc_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.","Type":"Description","Title":"batman-adv: hold claim backbone gateways by reference"}]}}}