{"id":"CVE-2026-93783","published":"2026-09-24T17:17:10.907","lastModified":"2026-09-25T13:17:18.830","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: RFCOMM: validate skb length in rfcomm_recv_frame\n\nrfcomm_recv_frame() casts skb->data to struct rfcomm_hdr and dereferences\nhdr->addr and hdr->ctrl without validating skb->len first. A truncated\nframe with skb->len less than the minimum header size causes an\nout-of-bounds read of uninitialized memory. Additionally, a zero-length\nframe causes skb->len-- to underflow to UINT_MAX, making\nskb_tail_pointer() read far past the buffer.\n\nCommit 23882b828c3c (\"Bluetooth: RFCOMM: validate skb length in MCC\nhandlers\") fixed the same class of missing-length-check bugs in the MCC\nsub-handlers, but the top-level rfcomm_recv_frame() was left unfixed.\nKMSAN reports:\n\n  BUG: KMSAN: uninit-value in rfcomm_run\n  ...\n  Uninit was created at:\n    __alloc_skb+0x474/0xb60\n    vhci_write+0xe9/0x870\n\nFix this by rejecting frames smaller than sizeof(struct rfcomm_hdr) + 1\n(the minimum frame must have a 3-byte header and a 1-byte FCS).","cvssScore":null,"cvssSeverity":null,"cvssVector":null,"cwes":[],"vendors":[],"products":[],"references":[{"url":"https://git.kernel.org/stable/c/67dc3b40fae71b6b11c71e7ff69bac0758818c05","tags":[]},{"url":"https://git.kernel.org/stable/c/b230e5bf501c5edaf2eb0991cb862ac142031d4b","tags":[]},{"url":"https://git.kernel.org/stable/c/bbc310caa2b6bf5fe42896ba27da0fbc12e4ac51","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":null}