{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-63891","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-07-19T07:54:57.019Z","datePublished":"2026-07-19T14:55:02.840Z","dateUpdated":"2026-07-19T14:55:02.840Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-07-19T14:55:02.840Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nthunderbolt: property: Cap recursion depth in __tb_property_parse_dir()\n\nA DIRECTORY entry's value field is used as the dir_offset for a\nrecursive call into __tb_property_parse_dir() with no depth counter.\nA crafted peer that chains DIRECTORY entries into a back-reference\nloop drives the parser until the kernel stack is exhausted and the\nguard page fires.  Any untrusted XDomain peer (cable, dock, in-line\ninspector, adjacent host) that reaches the PROPERTIES_REQUEST\ncontrol-plane exchange can trigger this without authentication.\n\nThread a depth counter through tb_property_parse() and\n__tb_property_parse_dir(), and reject blocks that exceed\nTB_PROPERTY_MAX_DEPTH = 8.  That is comfortably larger than any\nobserved legitimate XDomain layout.\n\nOperators who do not need XDomain host-to-host discovery can disable\nthe path entirely with thunderbolt.xdomain=0 on the kernel command\nline."}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/thunderbolt/property.c"],"versions":[{"version":"cdae7c07e3e3509eaabc18c1640a55dc5b99c179","lessThan":"2b5f47a710172c962ef42d1b732b04d2ad0dce21","status":"affected","versionType":"git"},{"version":"cdae7c07e3e3509eaabc18c1640a55dc5b99c179","lessThan":"95839a67ea56ca35732aad7f711404a3127cfe2d","status":"affected","versionType":"git"},{"version":"cdae7c07e3e3509eaabc18c1640a55dc5b99c179","lessThan":"0a84ab9271936c11e84e511bb52fc5682f8b6726","status":"affected","versionType":"git"},{"version":"cdae7c07e3e3509eaabc18c1640a55dc5b99c179","lessThan":"b4621e5ef63405c317a84b711faf3bd75b3c6a94","status":"affected","versionType":"git"},{"version":"cdae7c07e3e3509eaabc18c1640a55dc5b99c179","lessThan":"f31c6d220f455b5af63590302b30e1b932d14599","status":"affected","versionType":"git"},{"version":"cdae7c07e3e3509eaabc18c1640a55dc5b99c179","lessThan":"830c8a9b467e7d3a158483d37fa7dc13892b293a","status":"affected","versionType":"git"},{"version":"cdae7c07e3e3509eaabc18c1640a55dc5b99c179","lessThan":"ed9455ef4bd9babc90f92e526abe3fb68c1a8709","status":"affected","versionType":"git"},{"version":"cdae7c07e3e3509eaabc18c1640a55dc5b99c179","lessThan":"928abe19fbf0127003abcb1ea69cabc1c897d0ab","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/thunderbolt/property.c"],"versions":[{"version":"4.15","status":"affected"},{"version":"0","lessThan":"4.15","status":"unaffected","versionType":"semver"},{"version":"5.10.259","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.210","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.176","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.143","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.93","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.35","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.0.12","lessThanOrEqual":"7.0.*","status":"unaffected","versionType":"semver"},{"version":"7.1","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":"4.15","versionEndExcluding":"5.10.259"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"5.15.210"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"6.1.176"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"6.6.143"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"6.12.93"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"6.18.35"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"7.0.12"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.15","versionEndExcluding":"7.1"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/2b5f47a710172c962ef42d1b732b04d2ad0dce21"},{"url":"https://git.kernel.org/stable/c/95839a67ea56ca35732aad7f711404a3127cfe2d"},{"url":"https://git.kernel.org/stable/c/0a84ab9271936c11e84e511bb52fc5682f8b6726"},{"url":"https://git.kernel.org/stable/c/b4621e5ef63405c317a84b711faf3bd75b3c6a94"},{"url":"https://git.kernel.org/stable/c/f31c6d220f455b5af63590302b30e1b932d14599"},{"url":"https://git.kernel.org/stable/c/830c8a9b467e7d3a158483d37fa7dc13892b293a"},{"url":"https://git.kernel.org/stable/c/ed9455ef4bd9babc90f92e526abe3fb68c1a8709"},{"url":"https://git.kernel.org/stable/c/928abe19fbf0127003abcb1ea69cabc1c897d0ab"}],"title":"thunderbolt: property: Cap recursion depth in __tb_property_parse_dir()","x_generator":{"engine":"bippy-1.2.0"}}}}