{"api_version":"1","generated_at":"2026-07-20T14:42:17+00:00","cve":"CVE-2026-64121","urls":{"html":"https://cve.report/CVE-2026-64121","api":"https://cve.report/api/cve/CVE-2026-64121.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-64121","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-64121"},"summary":{"title":"net: ifb: report ethtool stats over num_tx_queues","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: ifb: report ethtool stats over num_tx_queues\n\nifb_dev_init() allocates dp->tx_private to dev->num_tx_queues\nentries via kzalloc_objs(*txp, dev->num_tx_queues). Both IFB\nper-queue RX and TX stats live in those entries: ifb_xmit() updates\ntxp->rx_stats using the skb queue mapping, ifb_ri_tasklet() updates\ntxp->tx_stats, and ifb_stats64() aggregates both over\ndev->num_tx_queues.\n\nThe ethtool stats callbacks instead size and walk the per-queue\nstats with dev->real_num_rx_queues and dev->real_num_tx_queues. With\nan asymmetric device where the RX queue count exceeds the TX queue\ncount, for example:\n\n    ip link add name ifb10 numtxqueues 1 numrxqueues 8 type ifb\n    ethtool -S ifb10\n\nifb_get_ethtool_stats() indexes past the tx_private allocation and\ncopies adjacent slab data through ETHTOOL_GSTATS.\n\nUse dev->num_tx_queues consistently for the stats strings, the\nstats count, and the stats data walks. This reports one RX stats\ngroup and one TX stats group for each backing ifb_q_private entry,\nwhich is the queue set IFB can actually populate.\n\nReproduced under UML+KASAN at v7.1-rc2:\n\n  BUG: KASAN: slab-out-of-bounds in ifb_fill_stats_data+0x3c/0xae\n  Read of size 8 at addr 0000000062dbd228 by task ethtool/36\n  ifb_fill_stats_data+0x3c/0xae\n  ifb_get_ethtool_stats+0xc0/0x129\n  __dev_ethtool+0x1ca5/0x363c\n  dev_ethtool+0x123/0x1b3\n  dev_ioctl+0x56c/0x744\n  sock_do_ioctl+0x15f/0x1b2\n  sock_ioctl+0x4d5/0x50a\n  sys_ioctl+0xd8b/0xde9\n\nWith the patch applied, the same UML+KASAN repro is silent and\nethtool -S ifb10 reports only the stats backed by the single\nallocated tx_private entry.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-07-19 16:17:53","updated_at":"2026-07-19 16:17:53"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/5db89c99566fc4728cc92e941d8e1975711e24b5","name":"https://git.kernel.org/stable/c/5db89c99566fc4728cc92e941d8e1975711e24b5","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/f8a5a76b4a683043c6eff2a060bcaa17f9316ad5","name":"https://git.kernel.org/stable/c/f8a5a76b4a683043c6eff2a060bcaa17f9316ad5","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/16bd798cb6d8337d7c3eea1adc412f31b5181d5b","name":"https://git.kernel.org/stable/c/16bd798cb6d8337d7c3eea1adc412f31b5181d5b","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/2638e1773904d7aa8f24c6e7fda2ed7d69df6fa4","name":"https://git.kernel.org/stable/c/2638e1773904d7aa8f24c6e7fda2ed7d69df6fa4","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/301a554e458e2f5ec47f2c336a7cb03b877f9fd6","name":"https://git.kernel.org/stable/c/301a554e458e2f5ec47f2c336a7cb03b877f9fd6","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/6afdb8113cb007f9332f59a9b7fd45731b8a9de5","name":"https://git.kernel.org/stable/c/6afdb8113cb007f9332f59a9b7fd45731b8a9de5","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-64121","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64121","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected a21ee5b2fcb8d6d3973446c5039e966c4cfe40d1 6afdb8113cb007f9332f59a9b7fd45731b8a9de5 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected a21ee5b2fcb8d6d3973446c5039e966c4cfe40d1 16bd798cb6d8337d7c3eea1adc412f31b5181d5b git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected a21ee5b2fcb8d6d3973446c5039e966c4cfe40d1 301a554e458e2f5ec47f2c336a7cb03b877f9fd6 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected a21ee5b2fcb8d6d3973446c5039e966c4cfe40d1 f8a5a76b4a683043c6eff2a060bcaa17f9316ad5 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected a21ee5b2fcb8d6d3973446c5039e966c4cfe40d1 2638e1773904d7aa8f24c6e7fda2ed7d69df6fa4 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected a21ee5b2fcb8d6d3973446c5039e966c4cfe40d1 5db89c99566fc4728cc92e941d8e1975711e24b5 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.17","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.17 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.1.175 6.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.142 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.92 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.34 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.0.11 7.0.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["drivers/net/ifb.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"6afdb8113cb007f9332f59a9b7fd45731b8a9de5","status":"affected","version":"a21ee5b2fcb8d6d3973446c5039e966c4cfe40d1","versionType":"git"},{"lessThan":"16bd798cb6d8337d7c3eea1adc412f31b5181d5b","status":"affected","version":"a21ee5b2fcb8d6d3973446c5039e966c4cfe40d1","versionType":"git"},{"lessThan":"301a554e458e2f5ec47f2c336a7cb03b877f9fd6","status":"affected","version":"a21ee5b2fcb8d6d3973446c5039e966c4cfe40d1","versionType":"git"},{"lessThan":"f8a5a76b4a683043c6eff2a060bcaa17f9316ad5","status":"affected","version":"a21ee5b2fcb8d6d3973446c5039e966c4cfe40d1","versionType":"git"},{"lessThan":"2638e1773904d7aa8f24c6e7fda2ed7d69df6fa4","status":"affected","version":"a21ee5b2fcb8d6d3973446c5039e966c4cfe40d1","versionType":"git"},{"lessThan":"5db89c99566fc4728cc92e941d8e1975711e24b5","status":"affected","version":"a21ee5b2fcb8d6d3973446c5039e966c4cfe40d1","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["drivers/net/ifb.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"5.17"},{"lessThan":"5.17","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.1.*","status":"unaffected","version":"6.1.175","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.142","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.92","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.34","versionType":"semver"},{"lessThanOrEqual":"7.0.*","status":"unaffected","version":"7.0.11","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.1.175","versionStartIncluding":"5.17","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.142","versionStartIncluding":"5.17","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.92","versionStartIncluding":"5.17","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.34","versionStartIncluding":"5.17","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.0.11","versionStartIncluding":"5.17","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1","versionStartIncluding":"5.17","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: ifb: report ethtool stats over num_tx_queues\n\nifb_dev_init() allocates dp->tx_private to dev->num_tx_queues\nentries via kzalloc_objs(*txp, dev->num_tx_queues). Both IFB\nper-queue RX and TX stats live in those entries: ifb_xmit() updates\ntxp->rx_stats using the skb queue mapping, ifb_ri_tasklet() updates\ntxp->tx_stats, and ifb_stats64() aggregates both over\ndev->num_tx_queues.\n\nThe ethtool stats callbacks instead size and walk the per-queue\nstats with dev->real_num_rx_queues and dev->real_num_tx_queues. With\nan asymmetric device where the RX queue count exceeds the TX queue\ncount, for example:\n\n    ip link add name ifb10 numtxqueues 1 numrxqueues 8 type ifb\n    ethtool -S ifb10\n\nifb_get_ethtool_stats() indexes past the tx_private allocation and\ncopies adjacent slab data through ETHTOOL_GSTATS.\n\nUse dev->num_tx_queues consistently for the stats strings, the\nstats count, and the stats data walks. This reports one RX stats\ngroup and one TX stats group for each backing ifb_q_private entry,\nwhich is the queue set IFB can actually populate.\n\nReproduced under UML+KASAN at v7.1-rc2:\n\n  BUG: KASAN: slab-out-of-bounds in ifb_fill_stats_data+0x3c/0xae\n  Read of size 8 at addr 0000000062dbd228 by task ethtool/36\n  ifb_fill_stats_data+0x3c/0xae\n  ifb_get_ethtool_stats+0xc0/0x129\n  __dev_ethtool+0x1ca5/0x363c\n  dev_ethtool+0x123/0x1b3\n  dev_ioctl+0x56c/0x744\n  sock_do_ioctl+0x15f/0x1b2\n  sock_ioctl+0x4d5/0x50a\n  sys_ioctl+0xd8b/0xde9\n\nWith the patch applied, the same UML+KASAN repro is silent and\nethtool -S ifb10 reports only the stats backed by the single\nallocated tx_private entry."}],"providerMetadata":{"dateUpdated":"2026-07-19T15:40:19.745Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/6afdb8113cb007f9332f59a9b7fd45731b8a9de5"},{"url":"https://git.kernel.org/stable/c/16bd798cb6d8337d7c3eea1adc412f31b5181d5b"},{"url":"https://git.kernel.org/stable/c/301a554e458e2f5ec47f2c336a7cb03b877f9fd6"},{"url":"https://git.kernel.org/stable/c/f8a5a76b4a683043c6eff2a060bcaa17f9316ad5"},{"url":"https://git.kernel.org/stable/c/2638e1773904d7aa8f24c6e7fda2ed7d69df6fa4"},{"url":"https://git.kernel.org/stable/c/5db89c99566fc4728cc92e941d8e1975711e24b5"}],"title":"net: ifb: report ethtool stats over num_tx_queues","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-64121","datePublished":"2026-07-19T15:40:19.745Z","dateReserved":"2026-07-19T07:54:57.036Z","dateUpdated":"2026-07-19T15:40:19.745Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-07-19 16:17:53","lastModifiedDate":"2026-07-19 16:17:53","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"64121","Ordinal":"1","Title":"net: ifb: report ethtool stats over num_tx_queues","CVE":"CVE-2026-64121","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"64121","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: ifb: report ethtool stats over num_tx_queues\n\nifb_dev_init() allocates dp->tx_private to dev->num_tx_queues\nentries via kzalloc_objs(*txp, dev->num_tx_queues). Both IFB\nper-queue RX and TX stats live in those entries: ifb_xmit() updates\ntxp->rx_stats using the skb queue mapping, ifb_ri_tasklet() updates\ntxp->tx_stats, and ifb_stats64() aggregates both over\ndev->num_tx_queues.\n\nThe ethtool stats callbacks instead size and walk the per-queue\nstats with dev->real_num_rx_queues and dev->real_num_tx_queues. With\nan asymmetric device where the RX queue count exceeds the TX queue\ncount, for example:\n\n    ip link add name ifb10 numtxqueues 1 numrxqueues 8 type ifb\n    ethtool -S ifb10\n\nifb_get_ethtool_stats() indexes past the tx_private allocation and\ncopies adjacent slab data through ETHTOOL_GSTATS.\n\nUse dev->num_tx_queues consistently for the stats strings, the\nstats count, and the stats data walks. This reports one RX stats\ngroup and one TX stats group for each backing ifb_q_private entry,\nwhich is the queue set IFB can actually populate.\n\nReproduced under UML+KASAN at v7.1-rc2:\n\n  BUG: KASAN: slab-out-of-bounds in ifb_fill_stats_data+0x3c/0xae\n  Read of size 8 at addr 0000000062dbd228 by task ethtool/36\n  ifb_fill_stats_data+0x3c/0xae\n  ifb_get_ethtool_stats+0xc0/0x129\n  __dev_ethtool+0x1ca5/0x363c\n  dev_ethtool+0x123/0x1b3\n  dev_ioctl+0x56c/0x744\n  sock_do_ioctl+0x15f/0x1b2\n  sock_ioctl+0x4d5/0x50a\n  sys_ioctl+0xd8b/0xde9\n\nWith the patch applied, the same UML+KASAN repro is silent and\nethtool -S ifb10 reports only the stats backed by the single\nallocated tx_private entry.","Type":"Description","Title":"net: ifb: report ethtool stats over num_tx_queues"}]}}}