{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-98030", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-25T10:19:56.070Z", "datePublished": "2026-09-25T10:23:46.959Z", "dateUpdated": "2026-10-19T09:12:35.325Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T09:12:35.325Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: dsa: bcm_sf2: bound the CFP rule dump by the caller's buffer size\n\nbcm_sf2_cfp_rule_get_all() walks the whole cfp.unique bitmap into\nrule_locs[] without consulting nfc->rule_cnt, which is how many entries\nthe caller had room for. ETHTOOL_GRXCLSRLALL requires no CAP_NET_ADMIN\nand the ioctl sizes the buffer from the rule_cnt userspace passes in, so\nonce an admin has installed CFP rules any user can ask for fewer slots\nthan there are rules and run off the end of the allocation. A rule_cnt\nof 0 leaves the buffer pointer NULL and the walk dereferences it." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The trigger is the local SIOCETHTOOL ioctl with ETHTOOL_GRXCLSRLALL on a bcm_sf2 DSA user port. The path is ethtool_get_rxnfc() -> dsa_user_get_rxnfc() -> bcm_sf2_get_rxnfc() -> bcm_sf2_cfp_rule_get_all(). The bad rule_cnt comes from userspace, and no packet from a remote peer is involved.\nAC:H - The overflow needs CFP rules installed beyond the default at bit 0 of cfp.unique, since the walk starts at index 1. Installing them via ETHTOOL_SRXCLSRLINS needs CAP_NET_ADMIN over the switch's netns, so the unprivileged attacker cannot create the rule state. Once rules exist, the bug fires every time.\nPR:L - ETHTOOL_GRXCLSRLALL is on ethtool's no-capability list in net/ethtool/ioctl.c, so any unprivileged local user who can open a socket in the netns holding the DSA port can send the dump request.\nUI:N - The attacker issues the ioctl themselves and picks rule_cnt. No other user has to act.\nS:U - Both the memory corruption and the leak stay inside the kernel's own security authority, with no VM or IOMMU boundary crossed.\nC:H - After the walk, nfc->rule_cnt holds the real rule count, which can be larger than the buffer. ethtool_rxnfc_copy_to_user() then copies rule_cnt*4 bytes from the undersized kcalloc buffer to userspace. That leaks up to about 1 KB of adjacent heap from a slab cache the attacker chooses.\nI:H - bcm_sf2_cfp_rule_get_all() writes u32 rule indices past a kcalloc(rule_cnt) buffer sized by the user. This is a heap out-of-bounds write into neighbouring objects in a slab cache the attacker picks, and it can corrupt kernel data structures.\nA:H - With rule_cnt=0 the rule_locs buffer stays NULL, so the walk writes through a NULL pointer and the kernel oopses. Any user can repeat this at will once rules are installed. Heap corruption from the out-of-bounds write can also crash the system." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/dsa/bcm_sf2_cfp.c" ], "versions": [ { "version": "7318166cacad158b46240f66250d7cc5a481653b", "lessThan": "ca49c526291d7cd3a5cb49b0edd7f50a5ae7176e", "status": "affected", "versionType": "git" }, { "version": "7318166cacad158b46240f66250d7cc5a481653b", "lessThan": "8e41ce02589c92356bfd8ef62f6ceff840546e1a", "status": "affected", "versionType": "git" }, { "version": "7318166cacad158b46240f66250d7cc5a481653b", "lessThan": "f2cf4ef2d94fc15fd2e21c131fc1ab3f76125bf4", "status": "affected", "versionType": "git" }, { "version": "7318166cacad158b46240f66250d7cc5a481653b", "lessThan": "f5e93162b3dd195bfda815e8f7a39aaf1d45437b", "status": "affected", "versionType": "git" }, { "version": "7318166cacad158b46240f66250d7cc5a481653b", "lessThan": "f1a2869b3629c0e8394b77b38cb9f19a018c653c", "status": "affected", "versionType": "git" }, { "version": "7318166cacad158b46240f66250d7cc5a481653b", "lessThan": "fd1a78c16b1f6978c09cf048e15f349732e4c707", "status": "affected", "versionType": "git" }, { "version": "7318166cacad158b46240f66250d7cc5a481653b", "lessThan": "b231b6d8516d3fe0d4bba549908e08d26a4531a5", "status": "affected", "versionType": "git" }, { "version": "7318166cacad158b46240f66250d7cc5a481653b", "lessThan": "cdb719f4b8596d9ccee2d56d204c2c4dce982f46", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/dsa/bcm_sf2_cfp.c" ], "versions": [ { "version": "4.11", "status": "affected" }, { "version": "0", "lessThan": "4.11", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.271", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.222", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.189", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.158", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.111", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.53", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.7", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.3", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "5.10.271" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "5.15.222" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "6.1.189" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "6.6.158" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "6.12.111" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "6.18.53" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "7.2.7" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.11", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/ca49c526291d7cd3a5cb49b0edd7f50a5ae7176e" }, { "url": "https://git.kernel.org/stable/c/8e41ce02589c92356bfd8ef62f6ceff840546e1a" }, { "url": "https://git.kernel.org/stable/c/f2cf4ef2d94fc15fd2e21c131fc1ab3f76125bf4" }, { "url": "https://git.kernel.org/stable/c/f5e93162b3dd195bfda815e8f7a39aaf1d45437b" }, { "url": "https://git.kernel.org/stable/c/f1a2869b3629c0e8394b77b38cb9f19a018c653c" }, { "url": "https://git.kernel.org/stable/c/fd1a78c16b1f6978c09cf048e15f349732e4c707" }, { "url": "https://git.kernel.org/stable/c/b231b6d8516d3fe0d4bba549908e08d26a4531a5" }, { "url": "https://git.kernel.org/stable/c/cdb719f4b8596d9ccee2d56d204c2c4dce982f46" } ], "title": "net: dsa: bcm_sf2: bound the CFP rule dump by the caller's buffer size", "x_generator": { "engine": "bippy-1.2.0" } } } }