Linux: Out-of-bounds Read
CVE-2026-64066 is a critical-severity out-of-bounds read vulnerability in Linux, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions 884c4c4f35e577aba6a0593c80cbea9ca5e6e2b8, 0256e79ce42101ad036edd4205bccca621ea0927, 8a8c0cfdf4658fc5b295b7fc87be56e0d76741f4 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 0.65% chance of exploitation within 30 days, higher than 52% of scored CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Update Linux to 884c4c4f35e577aba6a0593c80cbea9ca5e6e2b8 or 0256e79ce42101ad036edd4205bccca621ea0927 or 8a8c0cfdf4658fc5b295b7fc87be56e0d76741f4, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.18.34 or 7.0.11, whichever matches your release line, or a later version.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | ee4cdf7ba857a894ad1650d6ab77669cbbfa329e up to, but not including, 884c4c4f35e577aba6a0593c80cbea9ca5e6e2b8; ee4cdf7ba857a894ad1650d6ab77669cbbfa329e up to, but not including, 0256e79ce42101ad036edd4205bccca621ea0927; ee4cdf7ba857a894ad1650d6ab77669cbbfa329e up to, but not including, 8a8c0cfdf4658fc5b295b7fc87be56e0d76741f4; 6.12 | 884c4c4f35e577aba6a0593c80cbea9ca5e6e2b8, 0256e79ce42101ad036edd4205bccca621ea0927, 8a8c0cfdf4658fc5b295b7fc87be56e0d76741f4 |
| Linux | Linux Kernel | 6.12 up to, but not including, 6.18.34; 6.19 up to, but not including, 7.0.11; 7.1 | 6.18.34, 7.0.11 |
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
- NetworkCan be exploited remotely over a network, including the internet.
- 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:N/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: netfs: Fix netfs_read_to_pagecache() to pause on subreq failure Fix netfs_read_to_pagecache() so that it pauses the generation of new subrequests if an already-issued subrequest fails.
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
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.