CVE-2026-63915 nfc: hci: fix out-of-bounds read in HCP header parsing
A malicious NFC peer can trigger an out-of-bounds read and kernel panic via a zero-byte HCP frame, causing denial of service and potential information disclosure.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-63915?
CVE-2026-63915 is a high-severity memory corruption vulnerability in Linux, published on 19 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
nfc: hci: fix out-of-bounds read in HCP header parsing
Both nfc_hci_recv_from_llc() and nci_hci_data_received_cb() read packet->header from skb->data at function entry without first checking that the buffer holds at least one byte. A malicious NFC peer can send a 0-byte HCP frame that passes through the SHDLC layer and reaches these functions, causing an out-of-bounds heap read of packet->header. The same 0-byte frame, if queued as a non-final fragment, also causes the reassembly loop to underflow msg_len to UINT_MAX, triggering skb_over_panic() when the reassembled skb is written.
Fix this by adding a pskb_may_pull() check at the entry of each function before packet->header is first accessed. The existing pskb_may_pull() checks before the reassembled hcp_skb is cast to struct hcp_packet remain in place to guard the 2-byte HCP message header.
Which versions are affected by CVE-2026-63915?
How do I fix CVE-2026-63915?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-63915 being exploited?
There is no known exploitation of CVE-2026-63915 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-63915, DEBIAN-CVE-2026-63915, GHSA-jmh7-f679-ghx4, ROOT-OS-UBUNTU-2204-CVE-2026-63915, UBUNTU-CVE-2026-63915.