{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2025-21806", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2025-21806", "idYear": 2025, "status": "PUBLISHED", "publishedAt": "2025-02-27T20:00:58.918Z", "updatedAt": "2026-10-15T01:04:33.084Z", "importedAt": "2026-10-24T01:57:29.455Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "net: let net.core.dev_weight always be non-zero", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: let net.core.dev_weight always be non-zero\n\nThe following problem was encountered during stability test:\n\n(NULL net_device): NAPI poll function process_backlog+0x0/0x530 \\\n\treturned 1, exceeding its budget of 0.\n------------[ cut here ]------------\nlist_add double add: new=ffff88905f746f48, prev=ffff88905f746f48, \\\n\tnext=ffff88905f746e40.\nWARNING: CPU: 18 PID: 5462 at lib/list_debug.c:35 \\\n\t__list_add_valid_or_report+0xf3/0x130\nCPU: 18 UID: 0 PID: 5462 Comm: ping Kdump: loaded Not tainted 6.13.0-rc7+\nRIP: 0010:__list_add_valid_or_report+0xf3/0x130\nCall Trace:\n? __warn+0xcd/0x250\n? __list_add_valid_or_report+0xf3/0x130\nenqueue_to_backlog+0x923/0x1070\nnetif_rx_internal+0x92/0x2b0\n__netif_rx+0x15/0x170\nloopback_xmit+0x2ef/0x450\ndev_hard_start_xmit+0x103/0x490\n__dev_queue_xmit+0xeac/0x1950\nip_finish_output2+0x6cc/0x1620\nip_output+0x161/0x270\nip_push_pending_frames+0x155/0x1a0\nraw_sendmsg+0xe13/0x1550\n__sys_sendto+0x3bf/0x4e0\n__x64_sys_sendto+0xdc/0x1b0\ndo_syscall_64+0x5b/0x170\nentry_SYSCALL_64_after_hwframe+0x76/0x7e\n\nThe reproduction command is as follows:\n sysctl -w net.core.dev_weight=0\n ping 127.0.0.1\n\nThis is because when the napi's weight is set to 0, process_backlog() may\nreturn 0 and clear the NAPI_STATE_SCHED bit of napi->state, causing this\nnapi to be re-polled in net_rx_action() until __do_softirq() times out.\nSince the NAPI_STATE_SCHED bit has been cleared, napi_schedule_rps() can\nbe retriggered in enqueue_to_backlog(), causing this issue.\n\nMaking the napi's weight always non-zero solves this problem.\n\nTriggering this issue requires system-wide admin (setting is\nnot namespaced).", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "e3876605450979fe52a1a03e7eb78a89bf59e76a", "status": "affected", "versionType": "git", "lessThan": "d0e0f9c8218826926d7692980c98236d9f21fd3c" }, { "version": "e3876605450979fe52a1a03e7eb78a89bf59e76a", "status": "affected", "versionType": "git", "lessThan": "c337c08819a4ec49edfdcd8fc46fbee120d8a5b2" }, { "version": "e3876605450979fe52a1a03e7eb78a89bf59e76a", "status": "affected", "versionType": "git", "lessThan": "0e2f1d93d287d544d26f8ff293ea820a8079b9f8" }, { "version": "e3876605450979fe52a1a03e7eb78a89bf59e76a", "status": "affected", "versionType": "git", "lessThan": "5860abbf15eeb61838b5e32e721ba67b0aa84450" }, { "version": "e3876605450979fe52a1a03e7eb78a89bf59e76a", "status": "affected", "versionType": "git", "lessThan": "6ce38b5a6a49e65bad163162a54cb3f104c40b48" }, { "version": "e3876605450979fe52a1a03e7eb78a89bf59e76a", "status": "affected", "versionType": "git", "lessThan": "33e2168788f8fb5cb8bd4f36cb1ef37d1d34dada" }, { "version": "e3876605450979fe52a1a03e7eb78a89bf59e76a", "status": "affected", "versionType": "git", "lessThan": "1489824e5226a26841c70639ebd2d1aed390764b" }, { "version": "e3876605450979fe52a1a03e7eb78a89bf59e76a", "status": "affected", "versionType": "git", "lessThan": "d1f9f79fa2af8e3b45cffdeef66e05833480148a" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "2.6.12", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "2.6.12" }, { "version": "5.4.291", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.4.*" }, { "version": "5.10.235", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.10.*" }, { "version": "5.15.179", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "6.1.129", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.1.*" }, { "version": "6.6.76", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.6.*" }, { "version": "6.12.13", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.12.*" }, { "version": "6.13.2", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.13.*" }, { "version": "6.14", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }