{"id":"CVE-2026-63893","summary":"thunderbolt: property: Reject u32 wrap in tb_property_entry_valid()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nthunderbolt: property: Reject u32 wrap in tb_property_entry_valid()\n\nentry-\u003evalue is u32 and entry-\u003elength is u16; the sum is performed in\nu32 and wraps.  A malicious XDomain peer can pick\nvalue = 0xffffff00, length = 0x100 so the sum 0x100000000 wraps to 0\nand passes the \u003e block_len check.  tb_property_parse() then passes\nentry-\u003evalue to parse_dwdata() as a dword offset into the property\nblock, reading attacker-directed memory far past the allocation.\n\nFor TEXT-typed entries with the \"deviceid\" or \"vendorid\" keys this\nlands in xd-\u003edevice_name / xd-\u003evendor_name and is readable back via\nthe per-XDomain device_name / vendor_name sysfs attributes; the leak\nis NUL-bounded (kstrdup() stops at the first zero byte) and\nuntargeted (the attacker picks a delta, not an absolute address).\nDATA-typed entries are parsed into property-\u003evalue.data but not\ngenerically surfaced to userspace.\n\nUse check_add_overflow() so a wrapped sum is rejected.","modified":"2026-07-22T05:29:46.632239668Z","published":"2026-07-19T14:55:04.288Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63893.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/01deda0152066c6c955f0619114ea6afa070aaec"},{"type":"WEB","url":"https://git.kernel.org/stable/c/31b98e503ecca8077e5247253dd5425ab84bc96d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/5c06a3043ad944f087bb2ae0aae28d820bb9f460"},{"type":"WEB","url":"https://git.kernel.org/stable/c/6a63623621639acbb39bc2d9fb09559681716695"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8d4a758b407ab3de3be86d1ceadfa35d717d30c7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9fee50c4e1e42f6d3cbe30df584f9f648f626071"},{"type":"WEB","url":"https://git.kernel.org/stable/c/a47784aee77f33f786dc5d7375db821bdae68792"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e8a0b0a93a6ef958e70b1dd4930beb6dc0026b36"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63893.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-63893"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"cdae7c07e3e3509eaabc18c1640a55dc5b99c179"},{"fixed":"6a63623621639acbb39bc2d9fb09559681716695"},{"fixed":"e8a0b0a93a6ef958e70b1dd4930beb6dc0026b36"},{"fixed":"9fee50c4e1e42f6d3cbe30df584f9f648f626071"},{"fixed":"8d4a758b407ab3de3be86d1ceadfa35d717d30c7"},{"fixed":"5c06a3043ad944f087bb2ae0aae28d820bb9f460"},{"fixed":"31b98e503ecca8077e5247253dd5425ab84bc96d"},{"fixed":"a47784aee77f33f786dc5d7375db821bdae68792"},{"fixed":"01deda0152066c6c955f0619114ea6afa070aaec"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-63893.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.15.0"},{"fixed":"5.10.259"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.210"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.176"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.143"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.93"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.35"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.0.12"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-63893.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H"}]}