CVE-2026-90221 Details

In the Linux kernel, the following vulnerability has been resolved: nfc: nci: fix use of uninitialized memory in CORE_INIT_RSP parsing nci_core_init_rsp_packet_v1() and nci_core_init_rsp_packet_v2() parse the CORE_INIT_RSP packet without validating that the skb contains enough data. A malformed response (e.g. injected via virtual_ncidev) can declare a large num_supported_rf_interfaces while providing insufficient data, causing reads of uninitialized slab memory. This is later used in nci_init_complete_req(), triggering a KMSAN uninit-value warning. Add skb length checks before accessing packet fields: - Validate the skb has at least 1 byte for the status field. - Validate the skb can hold the fixed-size header before parsing. - In v2, bounds-check each variable-length rf_interface entry and its extension parameters within the parsing loop. - In v1, verify the skb is large enough for both the variable-length rf_interfaces array and the trailing rsp_2 structure.