{"api_version":"1","generated_at":"2026-07-23T15:12:48+00:00","cve":"CVE-2025-21806","urls":{"html":"https://cve.report/CVE-2025-21806","api":"https://cve.report/api/cve/CVE-2025-21806.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2025-21806","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2025-21806"},"summary":{"title":"net: let net.core.dev_weight always be non-zero","description":"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).","state":"PUBLISHED","assigner":"Linux","published_at":"2025-02-27 20:16:03","updated_at":"2026-05-12 13:16:37"},"problem_types":["NVD-CWE-noinfo"],"metrics":[{"version":"3.1","source":"nvd@nist.gov","type":"Primary","score":"5.5","severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","baseScore":5.5,"baseSeverity":"MEDIUM","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"}}],"references":[{"url":"https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html","name":"https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html","refsource":"af854a3a-2127-422b-91ae-364da2661108","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-503939.html","name":"https://cert-portal.siemens.com/productcert/html/ssa-503939.html","refsource":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/d0e0f9c8218826926d7692980c98236d9f21fd3c","name":"https://git.kernel.org/stable/c/d0e0f9c8218826926d7692980c98236d9f21fd3c","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/6ce38b5a6a49e65bad163162a54cb3f104c40b48","name":"https://git.kernel.org/stable/c/6ce38b5a6a49e65bad163162a54cb3f104c40b48","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/d1f9f79fa2af8e3b45cffdeef66e05833480148a","name":"https://git.kernel.org/stable/c/d1f9f79fa2af8e3b45cffdeef66e05833480148a","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-265688.html","name":"https://cert-portal.siemens.com/productcert/html/ssa-265688.html","refsource":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/c337c08819a4ec49edfdcd8fc46fbee120d8a5b2","name":"https://git.kernel.org/stable/c/c337c08819a4ec49edfdcd8fc46fbee120d8a5b2","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/1489824e5226a26841c70639ebd2d1aed390764b","name":"https://git.kernel.org/stable/c/1489824e5226a26841c70639ebd2d1aed390764b","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/0e2f1d93d287d544d26f8ff293ea820a8079b9f8","name":"https://git.kernel.org/stable/c/0e2f1d93d287d544d26f8ff293ea820a8079b9f8","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/33e2168788f8fb5cb8bd4f36cb1ef37d1d34dada","name":"https://git.kernel.org/stable/c/33e2168788f8fb5cb8bd4f36cb1ef37d1d34dada","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/5860abbf15eeb61838b5e32e721ba67b0aa84450","name":"https://git.kernel.org/stable/c/5860abbf15eeb61838b5e32e721ba67b0aa84450","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":["Patch"],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://lists.debian.org/debian-lts-announce/2025/03/msg00028.html","name":"https://lists.debian.org/debian-lts-announce/2025/03/msg00028.html","refsource":"af854a3a-2127-422b-91ae-364da2661108","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2025-21806","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-21806","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e3876605450979fe52a1a03e7eb78a89bf59e76a d0e0f9c8218826926d7692980c98236d9f21fd3c git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e3876605450979fe52a1a03e7eb78a89bf59e76a c337c08819a4ec49edfdcd8fc46fbee120d8a5b2 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e3876605450979fe52a1a03e7eb78a89bf59e76a 0e2f1d93d287d544d26f8ff293ea820a8079b9f8 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e3876605450979fe52a1a03e7eb78a89bf59e76a 5860abbf15eeb61838b5e32e721ba67b0aa84450 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e3876605450979fe52a1a03e7eb78a89bf59e76a 6ce38b5a6a49e65bad163162a54cb3f104c40b48 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e3876605450979fe52a1a03e7eb78a89bf59e76a 33e2168788f8fb5cb8bd4f36cb1ef37d1d34dada git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e3876605450979fe52a1a03e7eb78a89bf59e76a 1489824e5226a26841c70639ebd2d1aed390764b git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected e3876605450979fe52a1a03e7eb78a89bf59e76a d1f9f79fa2af8e3b45cffdeef66e05833480148a git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2.6.12","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 2.6.12 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.4.291 5.4.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.10.235 5.10.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.15.179 5.15.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.1.129 6.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.76 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.13 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.13.2 6.13.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.14 * original_commit_for_fix","platforms":[]},{"source":"ADP","vendor":"Siemens","product":"SIMATIC S7-1500 TM MFP - BIOS","version":"affected * custom","platforms":[]},{"source":"ADP","vendor":"Siemens","product":"SIMATIC S7-1500 TM MFP - GNU/Linux subsystem","version":"affected * custom","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[{"cve_year":"2025","cve_id":"21806","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"o","cpe4":"linux","cpe5":"linux_kernel","cpe6":"*","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"}],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"adp":[{"providerMetadata":{"dateUpdated":"2025-11-03T20:59:45.883Z","orgId":"af854a3a-2127-422b-91ae-364da2661108","shortName":"CVE"},"references":[{"url":"https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html"},{"url":"https://lists.debian.org/debian-lts-announce/2025/03/msg00028.html"}],"title":"CVE Program Container"},{"affected":[{"defaultStatus":"unknown","product":"SIMATIC S7-1500 TM MFP - BIOS","vendor":"Siemens","versions":[{"lessThan":"*","status":"affected","version":"0","versionType":"custom"}]},{"defaultStatus":"unknown","product":"SIMATIC S7-1500 TM MFP - GNU/Linux subsystem","vendor":"Siemens","versions":[{"lessThan":"*","status":"affected","version":"0","versionType":"custom"}]}],"providerMetadata":{"dateUpdated":"2026-05-12T12:03:57.348Z","orgId":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e","shortName":"siemens-SADP"},"references":[{"url":"https://cert-portal.siemens.com/productcert/html/ssa-265688.html"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-503939.html"}],"x_adpType":"supplier"}],"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/core/sysctl_net_core.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"d0e0f9c8218826926d7692980c98236d9f21fd3c","status":"affected","version":"e3876605450979fe52a1a03e7eb78a89bf59e76a","versionType":"git"},{"lessThan":"c337c08819a4ec49edfdcd8fc46fbee120d8a5b2","status":"affected","version":"e3876605450979fe52a1a03e7eb78a89bf59e76a","versionType":"git"},{"lessThan":"0e2f1d93d287d544d26f8ff293ea820a8079b9f8","status":"affected","version":"e3876605450979fe52a1a03e7eb78a89bf59e76a","versionType":"git"},{"lessThan":"5860abbf15eeb61838b5e32e721ba67b0aa84450","status":"affected","version":"e3876605450979fe52a1a03e7eb78a89bf59e76a","versionType":"git"},{"lessThan":"6ce38b5a6a49e65bad163162a54cb3f104c40b48","status":"affected","version":"e3876605450979fe52a1a03e7eb78a89bf59e76a","versionType":"git"},{"lessThan":"33e2168788f8fb5cb8bd4f36cb1ef37d1d34dada","status":"affected","version":"e3876605450979fe52a1a03e7eb78a89bf59e76a","versionType":"git"},{"lessThan":"1489824e5226a26841c70639ebd2d1aed390764b","status":"affected","version":"e3876605450979fe52a1a03e7eb78a89bf59e76a","versionType":"git"},{"lessThan":"d1f9f79fa2af8e3b45cffdeef66e05833480148a","status":"affected","version":"e3876605450979fe52a1a03e7eb78a89bf59e76a","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/core/sysctl_net_core.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"2.6.12"},{"lessThan":"2.6.12","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"5.4.*","status":"unaffected","version":"5.4.291","versionType":"semver"},{"lessThanOrEqual":"5.10.*","status":"unaffected","version":"5.10.235","versionType":"semver"},{"lessThanOrEqual":"5.15.*","status":"unaffected","version":"5.15.179","versionType":"semver"},{"lessThanOrEqual":"6.1.*","status":"unaffected","version":"6.1.129","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.76","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.13","versionType":"semver"},{"lessThanOrEqual":"6.13.*","status":"unaffected","version":"6.13.2","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"6.14","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.4.291","versionStartIncluding":"2.6.12","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.10.235","versionStartIncluding":"2.6.12","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.15.179","versionStartIncluding":"2.6.12","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.1.129","versionStartIncluding":"2.6.12","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.76","versionStartIncluding":"2.6.12","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.13","versionStartIncluding":"2.6.12","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.13.2","versionStartIncluding":"2.6.12","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.14","versionStartIncluding":"2.6.12","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"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)."}],"providerMetadata":{"dateUpdated":"2026-05-11T21:06:53.699Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/d0e0f9c8218826926d7692980c98236d9f21fd3c"},{"url":"https://git.kernel.org/stable/c/c337c08819a4ec49edfdcd8fc46fbee120d8a5b2"},{"url":"https://git.kernel.org/stable/c/0e2f1d93d287d544d26f8ff293ea820a8079b9f8"},{"url":"https://git.kernel.org/stable/c/5860abbf15eeb61838b5e32e721ba67b0aa84450"},{"url":"https://git.kernel.org/stable/c/6ce38b5a6a49e65bad163162a54cb3f104c40b48"},{"url":"https://git.kernel.org/stable/c/33e2168788f8fb5cb8bd4f36cb1ef37d1d34dada"},{"url":"https://git.kernel.org/stable/c/1489824e5226a26841c70639ebd2d1aed390764b"},{"url":"https://git.kernel.org/stable/c/d1f9f79fa2af8e3b45cffdeef66e05833480148a"}],"title":"net: let net.core.dev_weight always be non-zero","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2025-21806","datePublished":"2025-02-27T20:00:58.918Z","dateReserved":"2024-12-29T08:45:45.771Z","dateUpdated":"2026-05-12T12:03:57.348Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2025-02-27 20:16:03","lastModifiedDate":"2026-05-12 13:16:37","problem_types":["NVD-CWE-noinfo"],"metrics":{"cvssMetricV31":[{"source":"nvd@nist.gov","type":"Primary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","baseScore":5.5,"baseSeverity":"MEDIUM","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":1.8,"impactScore":3.6}]},"configurations":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.13","versionEndExcluding":"5.4.291","matchCriteriaId":"552A6C63-5778-4C1E-933C-E06FC7223B21"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"5.10.235","matchCriteriaId":"545121FA-DE31-4154-9446-C2000FB4104D"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.11","versionEndExcluding":"5.15.179","matchCriteriaId":"C708062C-4E1B-465F-AE6D-C09C46400875"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.16","versionEndExcluding":"6.1.129","matchCriteriaId":"2DA5009C-C9B9-4A1D-9B96-78427E8F232C"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.2","versionEndExcluding":"6.6.76","matchCriteriaId":"A6D70701-9CB6-4222-A957-00A419878993"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.7","versionEndExcluding":"6.12.13","matchCriteriaId":"2897389C-A8C3-4D69-90F2-E701B3D66373"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.13","versionEndExcluding":"6.13.2","matchCriteriaId":"6D4116B1-1BFD-4F23-BA84-169CC05FC5A3"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:2.6.12:-:*:*:*:*:*:*","matchCriteriaId":"6F62EECE-8FB1-4D57-85D8-CB9E23CF313C"}]}]}]},"legacy_mitre":{"record":{"CveYear":"2025","CveId":"21806","Ordinal":"1","Title":"net: let net.core.dev_weight always be non-zero","CVE":"CVE-2025-21806","Year":"2025"},"notes":[{"CveYear":"2025","CveId":"21806","Ordinal":"1","NoteData":"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).","Type":"Description","Title":"net: let net.core.dev_weight always be non-zero"}]}}}