Linux: Out-of-bounds Read
CVE-2026-43006 is a high-severity out-of-bounds read vulnerability in Linux, with a CVSS 3.1 base score of 7.1 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions 040a1e7e0e2f01851fec1dd2d96906f8636a9f75, 40170fc1a79c1b2e68f09ae6aac687b7305ae6f4, 111a12b422a8cfa93deabaef26fec48237163214 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 0.12% 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 040a1e7e0e2f01851fec1dd2d96906f8636a9f75 or 40170fc1a79c1b2e68f09ae6aac687b7305ae6f4 or 111a12b422a8cfa93deabaef26fec48237163214, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.18.22 or 6.19.12, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 8622b20f23ed165f48b8ca61503a107d17f8d585 up to, but not including, 040a1e7e0e2f01851fec1dd2d96906f8636a9f75; 8622b20f23ed165f48b8ca61503a107d17f8d585 up to, but not including, 40170fc1a79c1b2e68f09ae6aac687b7305ae6f4; 8622b20f23ed165f48b8ca61503a107d17f8d585 up to, but not including, 111a12b422a8cfa93deabaef26fec48237163214; 6.15 | 040a1e7e0e2f01851fec1dd2d96906f8636a9f75, 40170fc1a79c1b2e68f09ae6aac687b7305ae6f4, 111a12b422a8cfa93deabaef26fec48237163214 |
| Linux | Linux Kernel | 6.15 up to, but not including, 6.18.22; 6.19 up to, but not including, 6.19.12; 7.0 | 6.18.22, 6.19.12 |
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
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- 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
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H. Scored by CNA.
Official description
In the Linux kernel, the following vulnerability has been resolved: io_uring/rsrc: reject zero-length fixed buffer import validate_fixed_range() admits buf_addr at the exact end of the registered region when len is zero, because the check uses strict greater-than (buf_end > imu->ubuf + imu->len). io_import_fixed() then computes offset == imu->len, which causes the bvec skip logic to advance past the last bio_vec entry and read bv_offset from out-of-bounds slab memory. Return early from io_import_fixed() when len is zero. A zero-length import has no data to transfer and should not walk the bvec array at all. BUG: KASAN: slab-out-of-bounds in io_import_reg_buf+0x697/0x7f0 Read of size 4 at addr ffff888002bcc254 by task poc/103 Call Trace: io_import_reg_buf+0x697/0x7f0 io_write_fixed+0xd9/0x250 __io_issue_sqe+0xad/0x710 io_issue_sqe+0x7d/0x1100 io_submit_sqes+0x86a/0x23c0 __do_sys_io_uring_enter+0xa98/0x1590 Allocated by task 103: The buggy address is located 12 bytes to the right of allocated 584-byte region [ffff888002bcc000, ffff888002bcc248)
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
- 8.1 High severity
- 8.8 High severity
- 7.1 High severity
- 7.3 High severity
- 7.1 High severity
- 7.1 High severity
Spotted an error? Tell us.