{"id":"CVE-2026-74666","title":"In the Linux kernel, the following vulnerability has been resolved:\n\npacket: synchronize pressure clearing with ring reconfiguration\n\npacket_set_ring() updates the RX ring state under sk_receive_queue.lock,\nbut used to publish the tpacke…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\npacket: synchronize pressure clearing with ring reconfiguration\n\npacket_set_ring() updates the RX ring state under sk_receive_queue.lock,\nbut used to publish the tpacke…","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","cwe":["CWE-416"],"vendor":"Linux","product":"Linux","affected":["Linux >= 2ccdbaa6d55b0656244ba57c4b56765a0af76c0a < bf3c8e86bc8ad111be3f3136125e255344bcb3da","Linux >= 2ccdbaa6d55b0656244ba57c4b56765a0af76c0a < 8cfb2e71926a682f36c4240067d424074dd8f70f","Linux >= 2ccdbaa6d55b0656244ba57c4b56765a0af76c0a < f015c9de92b731814059a343b765c60c0196225c","Linux >= 2ccdbaa6d55b0656244ba57c4b56765a0af76c0a < cf8189b82bb93f219ab740e0346c919ad65ada62","Linux >= 2ccdbaa6d55b0656244ba57c4b56765a0af76c0a < ad740b4990347521f0db260d381f9f74e7b340ba","Linux >= 2ccdbaa6d55b0656244ba57c4b56765a0af76c0a < 2c7b5eb87b2b288cdbde825f21d2b83b2f5da747","Linux >= 2ccdbaa6d55b0656244ba57c4b56765a0af76c0a < a08196c3cc105947746ec21309edfbb60275fcdb","Linux >= 2ccdbaa6d55b0656244ba57c4b56765a0af76c0a < 1a35da325cac4d5bcad76a2aa943408a6f1d9000","Linux 4.2"],"published":"2026-08-22","updated":"2026-10-16","sourceUpdated":"2026-10-16T20:17:50.573","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-74666","references":[{"url":"https://git.kernel.org/stable/c/1a35da325cac4d5bcad76a2aa943408a6f1d9000","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/2c7b5eb87b2b288cdbde825f21d2b83b2f5da747","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/8cfb2e71926a682f36c4240067d424074dd8f70f","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/a08196c3cc105947746ec21309edfbb60275fcdb","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/ad740b4990347521f0db260d381f9f74e7b340ba","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/bf3c8e86bc8ad111be3f3136125e255344bcb3da","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/cf8189b82bb93f219ab740e0346c919ad65ada62","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/f015c9de92b731814059a343b765c60c0196225c","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-74666.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-74666"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2521363"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-74666"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-74666"},{"url":"https://kernelcve.org/list/?q=CVE-2026-74666"},{"url":"https://lore.kernel.org/linux-cve-announce/2026082228-CVE-2026-74666-f951@gregkh/T"}],"tags":["nvd","cve.org","csaf","vex","red-hat","score-dispute"],"epss":0.00129,"epssPercentile":0.02536,"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"total","timestamp":"2026-10-16T19:14:12.266180Z"},"scores":{"nvd":7.8,"vendor":5.5},"ingestedAt":"2026-10-14T13:30:58.531Z","slug":"CVE-2026-74666","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\npacket: synchronize pressure clearing with ring reconfiguration\n\npacket_set_ring() updates the RX ring state under sk_receive_queue.lock,\nbut used to publish the tpacket receive mode through po->prot_hook.func\nafter releasing that lock. packet_poll() and packet_recvmsg() can then\nrun the pressure clearing path after the ring has been cleared while\nstill seeing tpacket_rcv, causing __packet_rcv_has_room() to dereference\nstale or NULL ring storage.\n\nMove the existing receive hook assignment into the same\nsk_receive_queue.lock section as the ring state update. Keep the\nassignment otherwise unchanged, including on TX ring reconfiguration, to\navoid adding behavior changes that are not required for the fix.\n\nSerialize packet_recvmsg() pressure clearing with the same queue lock\nonly after PACKET_SOCK_PRESSURE has been observed. If the flag is clear\nand the socket has moved away from tpacket_rcv, packet_set_ring() has\nalready detached the socket and waited for synchronize_net(), so no new\npacket input can set the flag again.\n\npacket_poll() already holds sk_receive_queue.lock, so it uses the new\nunlocked helper directly.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · updated 2026-10-26 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-74666.json)","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}