CVE-2026-63891

CVE CVE-2026-63891EUVD EUVD-2026-45664Published 2026-07-19T14:55:02.000Z

What the advisory describes

In the Linux kernel, the following vulnerability has been resolved: thunderbolt: property: Cap recursion depth in __tb_property_parse_dir() A DIRECTORY entry's value field is used as the dir_offset for a recursive call into __tb_property_parse_dir() with no depth counter. A crafted peer that chains DIRECTORY entries into a back-reference loop drives the parser until the kernel stack is exhausted and the guard page fires. Any untrusted XDomain peer (cable, dock, in-line inspector, adjacent host) that reaches the PROPERTIES_REQUEST control-plane exchange can trigger this without authentication. Thread a depth counter through tb_property_parse() and __tb_property_parse_dir(), and reject blocks that exceed TB_PROPERTY_MAX_DEPTH = 8. That is comfortably larger than any observed legitimate XDomain layout. Operators who do not need XDomain host-to-host discovery can disable the path entirely with thunderbolt.xdomain=0 on the kernel command line.

Source: EUVD (ENISA), in the words of the advisory.

Products the advisory names

These come from the advisory itself, not from any check we performed.

Linux — Linux cdae7c07e3e3509eaabc18c1640a55dc5b99c179 <95839a67ea56ca35732aad7f711404a3127cfe2d; patch: 5.10.259; patch: 7.1; patch: 6.6.143; cdae7c07e3e3509eaabc18c1640a55dc5b99c179 <ed9455ef4bd9babc90f92e526abe3fb68c1a8709; patch: 6.18.35; cdae7c07e3e3509eaabc18c1640a55dc5b99c179 <f31c6d220f455b5af63590302b30e1b932d14599; patch: 0; 4.15; cdae7c07e3e3509eaabc18c1640a55dc5b99c179 <2b5f47a710172c962ef42d1b732b04d2ad0dce21; cdae7c07e3e3509eaabc18c1640a55dc5b99c179 <0a84ab9271936c11e84e511bb52fc5682f8b6726; patch: 5.15.210; cdae7c07e3e3509eaabc18c1640a55dc5b99c179 <b4621e5ef63405c317a84b711faf3bd75b3c6a94; patch: 7.0.12; cdae7c07e3e3509eaabc18c1640a55dc5b99c179 <928abe19fbf0127003abcb1ea69cabc1c897d0ab; patch: 6.1.176; cdae7c07e3e3509eaabc18c1640a55dc5b99c179 <830c8a9b467e7d3a158483d37fa7dc13892b293a; patch: 6.12.93

The versions shown are the advisory's own. Patchlage compares no version numbers and derives no judgement from them — which version is installed is something a person has to look up.

Carried in the product catalogue

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Linux — Linux

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