Linux: Out-of-bounds Read
CVE-2026-68098 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 remotely over the network by an attacker with a low-privileged account, without any action from a user. The record lists versions 05aa552bd69a96e090cbd45656e18cdc46524e20, 6d9d7aa4a2c99c31acfa28921c30b684110cf66c, b057a851129c6a084e7e393b62ca3abf6c2660bc 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 0.45% 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 05aa552bd69a96e090cbd45656e18cdc46524e20 or 6d9d7aa4a2c99c31acfa28921c30b684110cf66c or b057a851129c6a084e7e393b62ca3abf6c2660bc or f1eba60db813ec28732bf18b5f0a67ebac9c3100, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 up to, but not including, 05aa552bd69a96e090cbd45656e18cdc46524e20; e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 up to, but not including, 6d9d7aa4a2c99c31acfa28921c30b684110cf66c; e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 up to, but not including, b057a851129c6a084e7e393b62ca3abf6c2660bc; e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 up to, but not including, f1eba60db813ec28732bf18b5f0a67ebac9c3100; e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 up to, but not including, a0ebdaa79e10210d4e8ed9fe138e8f4d569719e3; e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 up to, but not including, 58d97fcd0bf1aee694e244cc28635b9df95b543b; 5.15 | 05aa552bd69a96e090cbd45656e18cdc46524e20, 6d9d7aa4a2c99c31acfa28921c30b684110cf66c, b057a851129c6a084e7e393b62ca3abf6c2660bc, f1eba60db813ec28732bf18b5f0a67ebac9c3100, a0ebdaa79e10210d4e8ed9fe138e8f4d569719e3, 58d97fcd0bf1aee694e244cc28635b9df95b543b |
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
- 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
- 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:L/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: ksmbd: bound DACL dedup walk to copied ACEs set_ntacl_dacl() can stop copying ACEs before consuming the full input DACL when size accounting overflows. When that happens, num_aces reflects only the ACEs that were actually copied into the output DACL, but set_posix_acl_entries_dacl() still receives nt_num_aces and uses it to walk the existing ACE array during dedup. That makes the dedup walk scan past the copied ACE array and inspect buffer tail that does not contain valid ACEs. Split the two meanings currently carried by the NT ACE count. Pass the number of copied NT ACEs to bound the dedup walk, and preserve the original "input DACL had NT ACEs" state separately for the Everyone/default ACL fallback. This keeps the dedup walk aligned with the ACEs that are actually present in the rebuilt DACL.
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.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other references
- git.kernel.org/stable/c/05aa552bd69a96e090cbd45656e18cdc46524e20
- git.kernel.org/stable/c/58d97fcd0bf1aee694e244cc28635b9df95b543b
- git.kernel.org/stable/c/6d9d7aa4a2c99c31acfa28921c30b684110cf66c
- git.kernel.org/stable/c/a0ebdaa79e10210d4e8ed9fe138e8f4d569719e3
- git.kernel.org/stable/c/b057a851129c6a084e7e393b62ca3abf6c2660bc
- git.kernel.org/stable/c/f1eba60db813ec28732bf18b5f0a67ebac9c3100
Recent Out-of-bounds Read vulnerabilities
- 7.1 High severity
- 9.8 Critical severity
- 8.1 High severity
- 8.3 High severity
- 7.1 High severity
- 9.1 Critical severity
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