Linux: Out-of-bounds Read
CVE-2026-63915 is a high-severity out-of-bounds read vulnerability in Linux, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited from the same local network by an unauthenticated attacker, without any action from a user. The record lists versions ed6d5d97dad0334a7f43d218753429cbe2f70a4f, b99366d74b535d0cadb1ef73e04639415d9ff3b7, 37382293f174b82a0616c8295e32b1fc8e13d1ed as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.35% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Linux to ed6d5d97dad0334a7f43d218753429cbe2f70a4f or b99366d74b535d0cadb1ef73e04639415d9ff3b7 or 37382293f174b82a0616c8295e32b1fc8e13d1ed or c4cc6b3b0013acb3ed0b2b60e57dfae98647fe98, whichever matches your release line, or a later version.
- Update Linux Kernel to 5.10.259 or 5.15.210 or 6.1.176 or 6.6.143, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 8b8d2e08bf0d50193931afd27482a59376b66b2b up to, but not including, ed6d5d97dad0334a7f43d218753429cbe2f70a4f; 8b8d2e08bf0d50193931afd27482a59376b66b2b up to, but not including, b99366d74b535d0cadb1ef73e04639415d9ff3b7; 8b8d2e08bf0d50193931afd27482a59376b66b2b up to, but not including, 37382293f174b82a0616c8295e32b1fc8e13d1ed; 8b8d2e08bf0d50193931afd27482a59376b66b2b up to, but not including, c4cc6b3b0013acb3ed0b2b60e57dfae98647fe98; 8b8d2e08bf0d50193931afd27482a59376b66b2b up to, but not including, 1905f5ec3641b2b234bb63549c8ca11ab85466eb; 8b8d2e08bf0d50193931afd27482a59376b66b2b up to, but not including, 22d41b176b9989efd21c3b2d3abf6728f05b9d9a; 8b8d2e08bf0d50193931afd27482a59376b66b2b up to, but not including, 83b1362edc9d6ae376c6f36da116e2c70f2e70a6; 8b8d2e08bf0d50193931afd27482a59376b66b2b up to, but not including, f040e590c035bfd9553fe79ee9585caf1b14d67b; and 1 more ranges | ed6d5d97dad0334a7f43d218753429cbe2f70a4f, b99366d74b535d0cadb1ef73e04639415d9ff3b7, 37382293f174b82a0616c8295e32b1fc8e13d1ed, c4cc6b3b0013acb3ed0b2b60e57dfae98647fe98, 1905f5ec3641b2b234bb63549c8ca11ab85466eb, 22d41b176b9989efd21c3b2d3abf6728f05b9d9a |
| Linux | Linux Kernel | 3.5 up to, but not including, 5.10.259; 5.11 up to, but not including, 5.15.210; 5.16 up to, but not including, 6.1.176; 6.2 up to, but not including, 6.6.143; 6.7 up to, but not including, 6.12.93; 6.13 up to, but not including, 6.18.35; 6.19 up to, but not including, 7.0.12; 7.1 | 5.10.259, 5.15.210, 6.1.176, 6.6.143, 6.12.93, 6.18.35 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- AdjacentThe attacker must be on the same local network segment.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA.
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.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Out-of-bounds Read
The product reads data past the end, or before the beginning, of the intended buffer.
How developers prevent this class of flaw
- Use a language that provides appropriate memory abstractions.
Timeline
- CVE record published.
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- git.kernel.org/stable/c/1905f5ec3641b2b234bb63549c8ca11ab85466eb
- git.kernel.org/stable/c/22d41b176b9989efd21c3b2d3abf6728f05b9d9a
- git.kernel.org/stable/c/37382293f174b82a0616c8295e32b1fc8e13d1ed
- git.kernel.org/stable/c/83b1362edc9d6ae376c6f36da116e2c70f2e70a6
- git.kernel.org/stable/c/b99366d74b535d0cadb1ef73e04639415d9ff3b7
- git.kernel.org/stable/c/c4cc6b3b0013acb3ed0b2b60e57dfae98647fe98
- git.kernel.org/stable/c/ed6d5d97dad0334a7f43d218753429cbe2f70a4f
- git.kernel.org/stable/c/f040e590c035bfd9553fe79ee9585caf1b14d67b
Recent Out-of-bounds Read vulnerabilities
- 7.1 High severity
- 7.8 High severity
- 7.3 High severity
- 7.1 High severity
- 7.8 High severity
- 9.8 Critical severity
Spotted an error? Tell us.