Answer in brief
CVE-2026-93783 records a Unknown severity vulnerability in Bluetooth: RFCOMM: validate skb length in rfcomm_recv_frame. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <67dc3b40fae71b6b11c71e7ff69bac0758818c05 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <bbc310caa2b6bf5fe42896ba27da0fbc12e4ac51 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <b230e5bf501c5edaf2eb0991cb862ac142031d4b || >=0 <6.12.111 || >=0 <6.18.53 | 67dc3b40fae71b6b11c71e7ff69bac0758818c05, bbc310caa2b6bf5fe42896ba27da0fbc12e4ac51, b230e5bf501c5edaf2eb0991cb862ac142031d4b, 6.12.111, 6.18.53 |
Published upstream
Sep 24, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 24, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 25, 2026
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: RFCOMM: validate skb length in rfcomm_recv_frame rfcomm_recv_frame() casts skb->data to struct rfcomm_hdr and dereferences hdr->addr and hdr->ctrl without validating skb->len first. A truncated frame with skb->len less than the minimum header size causes an out-of-bounds read of uninitialized memory. Additionally, a zero-length frame causes skb->len-- to underflow to UINT_MAX, making skb_tail_pointer() read far past the buffer. Commit 23882b828c3c ("Bluetooth: RFCOMM: validate skb length in MCC handlers") fixed the same class of missing-length-check bugs in the MCC sub-handlers, but the top-level rfcomm_recv_frame() was left unfixed. KMSAN reports: BUG: KMSAN: uninit-value in rfcomm_run ... Uninit was created at: __alloc_skb+0x474/0xb60 vhci_write+0xe9/0x870 Fix this by rejecting frames smaller than sizeof(struct rfcomm_hdr) + 1 (the minimum frame must have a 3-byte header and a 1-byte FCS).
Quoted source text, attributed separately from HOL analysis.