{"id":"CVE-2026-53069","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-53069","generatedAt":"2026-10-28T00:20:12.193Z","title":"In the Linux kernel, the following vulnerability has been resolved: net, bpf: fix null-ptr-deref in xdp_master_redirect() for down master syzkaller reported a kernel panic in bond_rr_gen_slave_id() reached via xdp_master_redirect().","description":"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(). 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.","published":"2026-06-24T17:17:20.000Z","lastModified":"2026-10-19T20:18:58.000Z","status":"Modified","sourceIdentifier":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","cvss":{"version":"3.1","score":7.5,"severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},"cwe":["CWE-476"],"affected":["linux/linux kernel"],"epss":{"score":0.0038,"percentile":0.31728,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (0.38%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"https://git.kernel.org/stable/c/183128da0406b1c10e6f60b7b9fe70788b9c8c1d","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/1921f91298d1388a0bb9db8f83800c998b649cb3","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/3128b294b426533c8d9162187446d93a8a160359","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/7bad93e99737e4a5c0c14ac50c05152cf4e28022","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/866d3d9b87751b1944168fd82615505e0c0fd6cf","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/acbf45bd584d924b320bee2a7fe2a26f64904d95","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ea690b3b6e58ae00979af8195b4cc24df466b65e","tags":["Patch"],"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-53069","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}