{"api_version":"1","generated_at":"2026-08-14T20:54:06+00:00","cve":"CVE-2026-68293","urls":{"html":"https://cve.report/CVE-2026-68293","api":"https://cve.report/api/cve/CVE-2026-68293.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-68293","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-68293"},"summary":{"title":"net/mlx5: Fix MCIA register buffer overflow on 32 dword reads","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/mlx5: Fix MCIA register buffer overflow on 32 dword reads\n\nThe MCIA register can return up to 32 dwords (128 bytes) when the device\nadvertises the mcia_32dwords capability, but struct\nmlx5_ifc_mcia_reg_bits only defines dword_0..11, leaving room for just\n12 dwords (48 bytes) of data.\n\nmlx5_query_mcia() clamps the read size to mlx5_mcia_max_bytes() and then\nmemcpy()s that many bytes out of the register, potentially reading past\nthe end of the 'out' buffer. On kernels built with FORTIFY_SOURCE this\nis caught as a buffer overflow while reading the module EEPROM via\nethtool:\n\n  detected buffer overflow in memcpy\n  kernel BUG at lib/string_helpers.c:1048!\n  RIP: 0010:fortify_panic+0x13/0x20\n  Call Trace:\n   mlx5_query_mcia.isra.0+0x200/0x210 [mlx5_core]\n   mlx5_query_module_eeprom_by_page+0x4a/0xa0 [mlx5_core]\n   mlx5e_get_module_eeprom_by_page+0xbb/0x120 [mlx5_core]\n   eeprom_prepare_data+0xf3/0x170\n   ethnl_default_doit+0xf1/0x3b0\n\nExtend the mcia_reg layout to 32 dwords.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-08-10 13:20:18","updated_at":"2026-08-13 23:17:28"},"problem_types":[],"metrics":[{"version":"3.1","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","score":"7.1","severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","baseScore":7.1,"baseSeverity":"HIGH","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"NONE","availabilityImpact":"HIGH"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"7.1","severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","data":{"baseScore":7.1,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","version":"3.1"}}],"references":[{"url":"https://git.kernel.org/stable/c/88b2a16ddac3357e3f1d528e758b51e2c945d546","name":"https://git.kernel.org/stable/c/88b2a16ddac3357e3f1d528e758b51e2c945d546","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/5be4eebd5a3a198dab0adcd550e1cadca79bdfed","name":"https://git.kernel.org/stable/c/5be4eebd5a3a198dab0adcd550e1cadca79bdfed","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/11c057d23465c7a5817a7284c896d19d54c0b616","name":"https://git.kernel.org/stable/c/11c057d23465c7a5817a7284c896d19d54c0b616","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/87b39a8c875ca744b7de69af0a8ef8874cffccf1","name":"https://git.kernel.org/stable/c/87b39a8c875ca744b7de69af0a8ef8874cffccf1","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-68293","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-68293","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 271907ee2f29cd1078fd219f0778fd824fb1971c 5be4eebd5a3a198dab0adcd550e1cadca79bdfed git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 271907ee2f29cd1078fd219f0778fd824fb1971c 87b39a8c875ca744b7de69af0a8ef8874cffccf1 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 271907ee2f29cd1078fd219f0778fd824fb1971c 88b2a16ddac3357e3f1d528e758b51e2c945d546 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 271907ee2f29cd1078fd219f0778fd824fb1971c 11c057d23465c7a5817a7284c896d19d54c0b616 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.18","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.18 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.101 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.42 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1.6 7.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2-rc5 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"68293","cve":"CVE-2026-68293","epss":"0.001850000","percentile":"0.083280000","score_date":"2026-08-13","updated_at":"2026-08-14 00:07:35"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["drivers/net/ethernet/mellanox/mlx5/core/port.c","include/linux/mlx5/mlx5_ifc.h"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"5be4eebd5a3a198dab0adcd550e1cadca79bdfed","status":"affected","version":"271907ee2f29cd1078fd219f0778fd824fb1971c","versionType":"git"},{"lessThan":"87b39a8c875ca744b7de69af0a8ef8874cffccf1","status":"affected","version":"271907ee2f29cd1078fd219f0778fd824fb1971c","versionType":"git"},{"lessThan":"88b2a16ddac3357e3f1d528e758b51e2c945d546","status":"affected","version":"271907ee2f29cd1078fd219f0778fd824fb1971c","versionType":"git"},{"lessThan":"11c057d23465c7a5817a7284c896d19d54c0b616","status":"affected","version":"271907ee2f29cd1078fd219f0778fd824fb1971c","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["drivers/net/ethernet/mellanox/mlx5/core/port.c","include/linux/mlx5/mlx5_ifc.h"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"5.18"},{"lessThan":"5.18","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.101","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.42","versionType":"semver"},{"lessThanOrEqual":"7.1.*","status":"unaffected","version":"7.1.6","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.2-rc5","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.101","versionStartIncluding":"5.18","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.42","versionStartIncluding":"5.18","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1.6","versionStartIncluding":"5.18","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2-rc5","versionStartIncluding":"5.18","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/mlx5: Fix MCIA register buffer overflow on 32 dword reads\n\nThe MCIA register can return up to 32 dwords (128 bytes) when the device\nadvertises the mcia_32dwords capability, but struct\nmlx5_ifc_mcia_reg_bits only defines dword_0..11, leaving room for just\n12 dwords (48 bytes) of data.\n\nmlx5_query_mcia() clamps the read size to mlx5_mcia_max_bytes() and then\nmemcpy()s that many bytes out of the register, potentially reading past\nthe end of the 'out' buffer. On kernels built with FORTIFY_SOURCE this\nis caught as a buffer overflow while reading the module EEPROM via\nethtool:\n\n  detected buffer overflow in memcpy\n  kernel BUG at lib/string_helpers.c:1048!\n  RIP: 0010:fortify_panic+0x13/0x20\n  Call Trace:\n   mlx5_query_mcia.isra.0+0x200/0x210 [mlx5_core]\n   mlx5_query_module_eeprom_by_page+0x4a/0xa0 [mlx5_core]\n   mlx5e_get_module_eeprom_by_page+0xbb/0x120 [mlx5_core]\n   eeprom_prepare_data+0xf3/0x170\n   ethnl_default_doit+0xf1/0x3b0\n\nExtend the mcia_reg layout to 32 dwords."}],"metrics":[{"cvssV3_1":{"baseScore":7.1,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","version":"3.1"},"scenarios":[{"lang":"en","value":"AV:L - The bug is reached only through local ethtool interfaces on the mlx5 netdev — the ETHTOOL_MSG_MODULE_EEPROM_GET genetlink message or the ETHTOOL_GMODULEEEPROM ioctl on a socket. No remote peer or received packet can trigger it.\nAC:L - A single ethtool module-EEPROM read of 128 bytes deterministically triggers the over-read on any adapter whose firmware advertises mcia_32dwords, which is the normal case on modern ConnectX hardware with a transceiver installed. No race, no memory-layout grooming, fully repeatable.\nPR:L - Both entry points check ns_capable(net->user_ns, CAP_NET_ADMIN), which is namespace-relative, so the root of an unprivileged user namespace owning a netns that holds an mlx5 VF/subfunction netdev (a standard SR-IOV container setup) can trigger it without any privilege in the initial namespace.\nUI:N - The attacker triggers the read entirely on their own by issuing an ethtool query; no action by another user or administrator is needed.\nS:U - The out-of-bounds read and its consequences are confined to the kernel of the same host; no VM, IOMMU, or other security-authority boundary is crossed.\nC:H - Up to 80 bytes of kernel stack adjacent to the 64-byte 'out' buffer are memcpy()'d into the EEPROM data returned to userspace, disclosing saved registers, pointers and potentially return addresses or the stack canary — enough to defeat KASLR and stack protection and aid further exploitation.\nI:N - The defect is purely a read overflow; the destination buffer is sized from the caller's own request length, so no kernel memory is written out of bounds and no data is modified.\nA:H - On the widely enabled CONFIG_FORTIFY_SOURCE the copy hits fortify_panic(), producing a kernel BUG/oops in mlx5_query_mcia() while rtnl/netdev locks are held (per the reported trace), wedging networking and panicking outright with panic_on_oops."}]}],"providerMetadata":{"dateUpdated":"2026-08-13T22:42:53.407Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/5be4eebd5a3a198dab0adcd550e1cadca79bdfed"},{"url":"https://git.kernel.org/stable/c/87b39a8c875ca744b7de69af0a8ef8874cffccf1"},{"url":"https://git.kernel.org/stable/c/88b2a16ddac3357e3f1d528e758b51e2c945d546"},{"url":"https://git.kernel.org/stable/c/11c057d23465c7a5817a7284c896d19d54c0b616"}],"title":"net/mlx5: Fix MCIA register buffer overflow on 32 dword reads","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-68293","datePublished":"2026-08-10T12:02:26.414Z","dateReserved":"2026-07-30T09:28:09.380Z","dateUpdated":"2026-08-13T22:42:53.407Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-08-10 13:20:18","lastModifiedDate":"2026-08-13 23:17:28","problem_types":[],"metrics":{"cvssMetricV31":[{"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","baseScore":7.1,"baseSeverity":"HIGH","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":1.8,"impactScore":5.2}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"68293","Ordinal":"1","Title":"net/mlx5: Fix MCIA register buffer overflow on 32 dword reads","CVE":"CVE-2026-68293","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"68293","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet/mlx5: Fix MCIA register buffer overflow on 32 dword reads\n\nThe MCIA register can return up to 32 dwords (128 bytes) when the device\nadvertises the mcia_32dwords capability, but struct\nmlx5_ifc_mcia_reg_bits only defines dword_0..11, leaving room for just\n12 dwords (48 bytes) of data.\n\nmlx5_query_mcia() clamps the read size to mlx5_mcia_max_bytes() and then\nmemcpy()s that many bytes out of the register, potentially reading past\nthe end of the 'out' buffer. On kernels built with FORTIFY_SOURCE this\nis caught as a buffer overflow while reading the module EEPROM via\nethtool:\n\n  detected buffer overflow in memcpy\n  kernel BUG at lib/string_helpers.c:1048!\n  RIP: 0010:fortify_panic+0x13/0x20\n  Call Trace:\n   mlx5_query_mcia.isra.0+0x200/0x210 [mlx5_core]\n   mlx5_query_module_eeprom_by_page+0x4a/0xa0 [mlx5_core]\n   mlx5e_get_module_eeprom_by_page+0xbb/0x120 [mlx5_core]\n   eeprom_prepare_data+0xf3/0x170\n   ethnl_default_doit+0xf1/0x3b0\n\nExtend the mcia_reg layout to 32 dwords.","Type":"Description","Title":"net/mlx5: Fix MCIA register buffer overflow on 32 dword reads"}]}}}