{"id":"CVE-2026-72126","title":"can: isotp: use unconditional synchronize_rcu() in isotp_release()","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\ncan: isotp: use unconditional synchronize_rcu() in isotp_release()\n\nisotp_notify() unregisters the (RCU) CAN filters via can_rx_unregister()\nand clears so->bound withou…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= 22bfa94db2ef6900c790884fa9461486516626e9 < 945d9894502cd9124f5d676181c542ed2000f7c0","Linux >= 14a4696bc3118ba49da28f79280e1d55603aa737 < 59672aa4bcd8d32172c1ff6a179583981d6acabc","Linux >= 14a4696bc3118ba49da28f79280e1d55603aa737 < 15413a082df69175c2f96aeab4c26fe1ff7cff03","Linux >= 14a4696bc3118ba49da28f79280e1d55603aa737 < 6280eda96e0707264849fa7d036fed873c1f8a6d","Linux >= 14a4696bc3118ba49da28f79280e1d55603aa737 < cb6abc584a1bfab107ac003d64948a4aef1730aa","Linux >= 14a4696bc3118ba49da28f79280e1d55603aa737 < b88a511308779c225005d7994b8744561bdbafbc","Linux >= 14a4696bc3118ba49da28f79280e1d55603aa737 < b8278ff605187ef3fa0f2705e93251cce4c4f8ee","Linux >= 14a4696bc3118ba49da28f79280e1d55603aa737 < 9b1a02e0d980ac6b0e36a90378f847062f81d7e4","Linux 80c6ddf771df2ef786f28c1ca5919b3f1080091b","Linux ebf91625b3e404bd2b4b694c7ee71c1e8f8bd08f","Linux >= 5.10.50 < 5.10.261","Linux >= 5.12.17 < 5.13","Linux >= 5.13.2 < 5.14","Linux 5.14"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-10-16T18:42:20.650624Z"},"published":"2026-08-15","updated":"2026-10-16","sourceUpdated":"2026-10-16T18:44:58.135Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-72126","references":[{"url":"https://git.kernel.org/stable/c/945d9894502cd9124f5d676181c542ed2000f7c0"},{"url":"https://git.kernel.org/stable/c/59672aa4bcd8d32172c1ff6a179583981d6acabc"},{"url":"https://git.kernel.org/stable/c/15413a082df69175c2f96aeab4c26fe1ff7cff03"},{"url":"https://git.kernel.org/stable/c/6280eda96e0707264849fa7d036fed873c1f8a6d"},{"url":"https://git.kernel.org/stable/c/cb6abc584a1bfab107ac003d64948a4aef1730aa"},{"url":"https://git.kernel.org/stable/c/b88a511308779c225005d7994b8744561bdbafbc"},{"url":"https://git.kernel.org/stable/c/b8278ff605187ef3fa0f2705e93251cce4c4f8ee"},{"url":"https://git.kernel.org/stable/c/9b1a02e0d980ac6b0e36a90378f847062f81d7e4"}],"tags":["cve.org"],"epss":0.00171,"epssPercentile":0.06041,"ingestedAt":"2026-10-16T19:46:24.428Z","slug":"CVE-2026-72126","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\ncan: isotp: use unconditional synchronize_rcu() in isotp_release()\n\nisotp_notify() unregisters the (RCU) CAN filters via can_rx_unregister()\nand clears so->bound without waiting for a grace period. isotp_release()\nuses so->bound to decide whether it needs to call synchronize_rcu()\nbefore cancelling so->rxtimer, so when NETDEV_UNREGISTER runs first it\nskips that synchronize_rcu() and can cancel the timer while an\nin-flight isotp_rcv() is still executing and about to re-arm it via\nisotp_send_fc(), leading to a use-after-free timer callback on the\nfreed socket.\n\nsakisho-bot remarked a problem with rtnl_lock held in isotp_notify(),\ntherefore make isotp_release() always call synchronize_rcu() before\ncancelling the timers, regardless of so->bound. This still closes the\noriginal race (isotp_notify() clearing so->bound without waiting for\nin-flight isotp_rcv() callers before isotp_release() cancels the RX\ntimer) without adding any RCU wait to the netdevice notifier path.\n\n## Affected\n\n- `Linux >= 22bfa94db2ef6900c790884fa9461486516626e9 < 945d9894502cd9124f5d676181c542ed2000f7c0`\n- `Linux >= 14a4696bc3118ba49da28f79280e1d55603aa737 < 59672aa4bcd8d32172c1ff6a179583981d6acabc`\n- `Linux >= 14a4696bc3118ba49da28f79280e1d55603aa737 < 15413a082df69175c2f96aeab4c26fe1ff7cff03`\n- `Linux >= 14a4696bc3118ba49da28f79280e1d55603aa737 < 6280eda96e0707264849fa7d036fed873c1f8a6d`\n- `Linux >= 14a4696bc3118ba49da28f79280e1d55603aa737 < cb6abc584a1bfab107ac003d64948a4aef1730aa`\n- `Linux >= 14a4696bc3118ba49da28f79280e1d55603aa737 < b88a511308779c225005d7994b8744561bdbafbc`\n- `Linux >= 14a4696bc3118ba49da28f79280e1d55603aa737 < b8278ff605187ef3fa0f2705e93251cce4c4f8ee`\n- `Linux >= 14a4696bc3118ba49da28f79280e1d55603aa737 < 9b1a02e0d980ac6b0e36a90378f847062f81d7e4`\n- `Linux 80c6ddf771df2ef786f28c1ca5919b3f1080091b`\n- `Linux ebf91625b3e404bd2b4b694c7ee71c1e8f8bd08f`\n- `Linux >= 5.10.50 < 5.10.261`\n- `Linux >= 5.12.17 < 5.13`\n- `Linux >= 5.13.2 < 5.14`\n- `Linux 5.14`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}