{"id":"CVE-2026-53069","title":"net, bpf: fix null-ptr-deref in xdp_master_redirect() for down master","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet, bpf: fix null-ptr-deref in xdp_master_redirect() for down master\n\nsyzkaller reported a kernel panic in bond_rr_gen_slave_id() reached via\nxdp_master_redirect(). Fu…","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= 879af96ffd72706c6e3278ea6b45b0b0e37ec5d7 < 3128b294b426533c8d9162187446d93a8a160359","Linux >= 879af96ffd72706c6e3278ea6b45b0b0e37ec5d7 < acbf45bd584d924b320bee2a7fe2a26f64904d95","Linux >= 879af96ffd72706c6e3278ea6b45b0b0e37ec5d7 < 866d3d9b87751b1944168fd82615505e0c0fd6cf","Linux >= 879af96ffd72706c6e3278ea6b45b0b0e37ec5d7 < 183128da0406b1c10e6f60b7b9fe70788b9c8c1d","Linux >= 879af96ffd72706c6e3278ea6b45b0b0e37ec5d7 < 7bad93e99737e4a5c0c14ac50c05152cf4e28022","Linux >= 879af96ffd72706c6e3278ea6b45b0b0e37ec5d7 < ea690b3b6e58ae00979af8195b4cc24df466b65e","Linux >= 879af96ffd72706c6e3278ea6b45b0b0e37ec5d7 < 1921f91298d1388a0bb9db8f83800c998b649cb3","Linux 5.15"],"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"partial","timestamp":"2026-10-16T15:25:03.791901Z"},"published":"2026-06-24","updated":"2026-10-16","sourceUpdated":"2026-10-16T15:31:30.133Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-53069","references":[{"url":"https://git.kernel.org/stable/c/3128b294b426533c8d9162187446d93a8a160359"},{"url":"https://git.kernel.org/stable/c/acbf45bd584d924b320bee2a7fe2a26f64904d95"},{"url":"https://git.kernel.org/stable/c/866d3d9b87751b1944168fd82615505e0c0fd6cf"},{"url":"https://git.kernel.org/stable/c/183128da0406b1c10e6f60b7b9fe70788b9c8c1d"},{"url":"https://git.kernel.org/stable/c/7bad93e99737e4a5c0c14ac50c05152cf4e28022"},{"url":"https://git.kernel.org/stable/c/ea690b3b6e58ae00979af8195b4cc24df466b65e"},{"url":"https://git.kernel.org/stable/c/1921f91298d1388a0bb9db8f83800c998b649cb3"}],"tags":["cve.org"],"epss":0.0038,"epssPercentile":0.3039,"ingestedAt":"2026-10-16T17:24:46.728Z","slug":"CVE-2026-53069","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnet, bpf: fix null-ptr-deref in xdp_master_redirect() for down master\n\nsyzkaller reported a kernel panic in bond_rr_gen_slave_id() reached via\nxdp_master_redirect(). Full decoded trace:\n\n  https://syzkaller.appspot.com/bug?extid=80e046b8da2820b6ba73\n\nbond_rr_gen_slave_id() dereferences bond->rr_tx_counter, a per-CPU\ncounter that bonding only allocates in bond_open() when the mode is\nround-robin. If the bond device was never brought up, rr_tx_counter\nstays NULL.\n\nThe XDP redirect path can still reach that code on a bond that was\nnever opened: bpf_master_redirect_enabled_key is a global static key,\nso as soon as any bond device has native XDP attached, the\nXDP_TX -> xdp_master_redirect() interception is enabled for every\nslave system-wide. The path xdp_master_redirect() ->\nbond_xdp_get_xmit_slave() -> bond_xdp_xmit_roundrobin_slave_get() ->\nbond_rr_gen_slave_id() then runs against a bond that has no\nrr_tx_counter and crashes.\n\nFix this in the generic xdp_master_redirect() by refusing to call into\nthe master's ->ndo_xdp_get_xmit_slave() when the master device is not\nup. IFF_UP is only set after ->ndo_open() has successfully returned,\nso this reliably excludes masters whose XDP state has not been fully\ninitialized. Drop the frame with XDP_ABORTED so the exception is\nvisible via trace_xdp_exception() rather than silently falling through.\nThis is not specific to bonding: any current or future master that\ndefers XDP state allocation to ->ndo_open() is protected.\n\n## Affected\n\n- `Linux >= 879af96ffd72706c6e3278ea6b45b0b0e37ec5d7 < 3128b294b426533c8d9162187446d93a8a160359`\n- `Linux >= 879af96ffd72706c6e3278ea6b45b0b0e37ec5d7 < acbf45bd584d924b320bee2a7fe2a26f64904d95`\n- `Linux >= 879af96ffd72706c6e3278ea6b45b0b0e37ec5d7 < 866d3d9b87751b1944168fd82615505e0c0fd6cf`\n- `Linux >= 879af96ffd72706c6e3278ea6b45b0b0e37ec5d7 < 183128da0406b1c10e6f60b7b9fe70788b9c8c1d`\n- `Linux >= 879af96ffd72706c6e3278ea6b45b0b0e37ec5d7 < 7bad93e99737e4a5c0c14ac50c05152cf4e28022`\n- `Linux >= 879af96ffd72706c6e3278ea6b45b0b0e37ec5d7 < ea690b3b6e58ae00979af8195b4cc24df466b65e`\n- `Linux >= 879af96ffd72706c6e3278ea6b45b0b0e37ec5d7 < 1921f91298d1388a0bb9db8f83800c998b649cb3`\n- `Linux 5.15`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}