CVE-2026-64380
Last modified
CVE-2026-64380 is a high-severity vulnerability rated 8.2/10 on the CVSS scale. In the Linux kernel, the following vulnerability has been resolved: smb: client: harden POSIX SID length parsing posix_info_sid_size() reads sid[1] to obtain the subauthority count, but its existing boundary check still accepts buffers with only one remaining byte. Require two bytes before reading sid[1] so all client paths that reuse the helper reject truncated POSIX SIDs safely.. EPSS estimates a 0.44% chance of exploitation in the next 30 days.
Description
In the Linux kernel, the following vulnerability has been resolved: smb: client: harden POSIX SID length parsing posix_info_sid_size() reads sid[1] to obtain the subauthority count, but its existing boundary check still accepts buffers with only one remaining byte. Require two bytes before reading sid[1] so all client paths that reuse the helper reject truncated POSIX SIDs safely.
Metrics
Affected Software
| Vendor | Product | Versions | Update |
|---|---|---|---|
| Linux | Linux Kernel | >= 5.7, < 5.10.261 | — |
| Linux | Linux Kernel | >= 5.11, < 5.15.212 | — |
| Linux | Linux Kernel | >= 5.16, < 6.1.178 | — |
| Linux | Linux Kernel | >= 6.2, < 6.6.145 | — |
| Linux | Linux Kernel | >= 6.7, < 6.12.96 | — |
| Linux | Linux Kernel | >= 6.13, < 6.18.39 | — |
| Linux | Linux Kernel | >= 6.19, < 7.1.4 | — |
| Linux | Linux Kernel | 7.2 | Rc1 |
References
Timeline
- Published
- Last Modified
- Status
- Analyzed
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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