{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-64545", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-19T15:36:31.795Z", "datePublished": "2026-07-27T20:10:36.659Z", "dateUpdated": "2026-08-17T04:57:22.161Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T04:57:22.161Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet, bpf: check master for NULL in xdp_master_redirect()\n\nxdp_master_redirect() dereferences the result of\nnetdev_master_upper_dev_get_rcu() without a NULL check, but that helper\nreturns NULL when the receiving device has no upper-master adjacency.\n\nThe reach guard only checks netif_is_bond_slave(). On bond slave release\nbond_upper_dev_unlink() drops the upper-master adjacency before clearing\nIFF_SLAVE, so an XDP_TX reaching xdp_master_redirect() in that window\nstill passes netif_is_bond_slave() while master is already NULL, and\nfaults on master->flags at offset 0xb0:\n\n BUG: kernel NULL pointer dereference, address: 00000000000000b0\n RIP: 0010:xdp_master_redirect (net/core/filter.c:4432)\n Call Trace:\n xdp_master_redirect (net/core/filter.c:4432)\n bpf_prog_run_generic_xdp (include/net/xdp.h:700)\n do_xdp_generic (net/core/dev.c:5608)\n __netif_receive_skb_one_core (net/core/dev.c:6204)\n process_backlog (net/core/dev.c:6319)\n __napi_poll (net/core/dev.c:7729)\n net_rx_action (net/core/dev.c:7792)\n handle_softirqs (kernel/softirq.c:622)\n __dev_queue_xmit (include/linux/bottom_half.h:33)\n packet_sendmsg (net/packet/af_packet.c:3082)\n __sys_sendto (net/socket.c:2252)\n Kernel panic - not syncing: Fatal exception in interrupt\n\nThe missing check dates back to the original code; commit 1921f91298d1\n(\"net, bpf: fix null-ptr-deref in xdp_master_redirect() for down master\")\nlater added the master->flags read where the fault now lands but kept the\nunconditional deref. Check master for NULL before use; a NULL master is\ntreated the same as one that is not up." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "baseScore": 7.5, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:N - The faulting path is the XDP receive hook — packets arriving on a bond slave drive `bpf_prog_run_xdp`/`do_xdp_generic` → `xdp_master_redirect()`, so a remote attacker sending traffic to a bonded interface running an XDP_TX program (XDP load balancers/DDoS scrubbers on bonded uplinks are a mainstream deployment) supplies the triggering packets with no local access.\nAC:L - The attacker controls the packet side of the race and can sustain line-rate traffic so the multi-microsecond window between adjacency teardown and `IFF_SLAVE` clearing is hit essentially deterministically; where the attacker also holds the network configuration side (container/netns with bond and XDP control) both sides of the race are attacker-driven, which the kernel guidance classes as Low.\nPR:N - No credentials or authentication are needed to send frames to a bonded interface, and the fault occurs in softirq during receive processing before any socket, filesystem, or user-level authorization is consulted — matching the PR:N treatment of the sibling fix CVE-2026-53069 in this same function.\nUI:N - No victim action is required; the slave-release window is reached by routine and externally-induced events (bond reconfiguration, `bond_enslave` rollback, NIC hotplug/`NETDEV_UNREGISTER`), and the attacker need only keep traffic flowing.\nS:U - The NULL dereference and its consequences are confined to the kernel's own security authority; no hypervisor, IOMMU, or sandbox boundary is crossed.\nC:N - The bug is a read of `master->flags` at fixed offset 0xb0 from a NULL pointer, which faults immediately; no memory contents are returned to the attacker and no kernel addresses are disclosed.\nI:N - There is no write primitive — the defect is a read-side dereference that faults before `master->netdev_ops->ndo_xdp_get_xmit_slave()` is reached, so no kernel data or control flow is modified.\nA:H - The dereference happens in softirq/interrupt context, producing \"Kernel panic - not syncing: Fatal exception in interrupt\" — a complete system crash rather than a recoverable oops, and it can be re-triggered on every reboot as long as traffic and bond reconfiguration continue." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/core/filter.c" ], "versions": [ { "version": "879af96ffd72706c6e3278ea6b45b0b0e37ec5d7", "lessThan": "c99ca049e910d61ddbd28cc2c47242f2bfbb4970", "status": "affected", "versionType": "git" }, { "version": "879af96ffd72706c6e3278ea6b45b0b0e37ec5d7", "lessThan": "e2a56441233131fe18a76001de347ecda217e40c", "status": "affected", "versionType": "git" }, { "version": "879af96ffd72706c6e3278ea6b45b0b0e37ec5d7", "lessThan": "3876318ea54e83eb70982b8280a3c5e4e32269bf", "status": "affected", "versionType": "git" }, { "version": "879af96ffd72706c6e3278ea6b45b0b0e37ec5d7", "lessThan": "4edbcacca09f92b85d3951b6add11894b20a84bc", "status": "affected", "versionType": "git" }, { "version": "879af96ffd72706c6e3278ea6b45b0b0e37ec5d7", "lessThan": "03b743586a2469744e96e9c1015096d07240935d", "status": "affected", "versionType": "git" }, { "version": "879af96ffd72706c6e3278ea6b45b0b0e37ec5d7", "lessThan": "89c103d702b25ceb2d097faf854deb47b53b17ff", "status": "affected", "versionType": "git" }, { "version": "879af96ffd72706c6e3278ea6b45b0b0e37ec5d7", "lessThan": "e82d8cc4321c373dc46e741cd2dfdaa7921fddb7", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/core/filter.c" ], "versions": [ { "version": "5.15", "status": "affected" }, { "version": "0", "lessThan": "5.15", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.212", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.178", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.145", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.97", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.40", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.5", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "5.15.212" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.1.178" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.6.145" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.12.97" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.18.40" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "7.1.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/c99ca049e910d61ddbd28cc2c47242f2bfbb4970" }, { "url": "https://git.kernel.org/stable/c/e2a56441233131fe18a76001de347ecda217e40c" }, { "url": "https://git.kernel.org/stable/c/3876318ea54e83eb70982b8280a3c5e4e32269bf" }, { "url": "https://git.kernel.org/stable/c/4edbcacca09f92b85d3951b6add11894b20a84bc" }, { "url": "https://git.kernel.org/stable/c/03b743586a2469744e96e9c1015096d07240935d" }, { "url": "https://git.kernel.org/stable/c/89c103d702b25ceb2d097faf854deb47b53b17ff" }, { "url": "https://git.kernel.org/stable/c/e82d8cc4321c373dc46e741cd2dfdaa7921fddb7" } ], "title": "net, bpf: check master for NULL in xdp_master_redirect()", "x_generator": { "engine": "bippy-1.2.0" } } } }