Linux: Out-of-bounds Write
CVE-2025-38533 is a high-severity out-of-bounds write vulnerability in Linux, with a CVSS 3.1 base score of 7.8 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 027701180a7bcb64c42eab291133ef0c87b5b6c5, ba7c793f96c1c2b944bb6f423d7243f3afc30fe9, 05c37b574997892a40a0e9b9b88a481566b2367d 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 0.33% 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 027701180a7bcb64c42eab291133ef0c87b5b6c5 or ba7c793f96c1c2b944bb6f423d7243f3afc30fe9 or 05c37b574997892a40a0e9b9b88a481566b2367d or 5fd77cc6bd9b368431a815a780e407b7781bcca0, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.6.100 or 6.12.40 or 6.15.8, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 3c47e8ae113a68da47987750d9896e325d0aeedd up to, but not including, 027701180a7bcb64c42eab291133ef0c87b5b6c5; 3c47e8ae113a68da47987750d9896e325d0aeedd up to, but not including, ba7c793f96c1c2b944bb6f423d7243f3afc30fe9; 3c47e8ae113a68da47987750d9896e325d0aeedd up to, but not including, 05c37b574997892a40a0e9b9b88a481566b2367d; 3c47e8ae113a68da47987750d9896e325d0aeedd up to, but not including, 5fd77cc6bd9b368431a815a780e407b7781bcca0; 6.3 | 027701180a7bcb64c42eab291133ef0c87b5b6c5, ba7c793f96c1c2b944bb6f423d7243f3afc30fe9, 05c37b574997892a40a0e9b9b88a481566b2367d, 5fd77cc6bd9b368431a815a780e407b7781bcca0 |
| Linux | Linux Kernel | 6.3 up to, but not including, 6.6.100; 6.7 up to, but not including, 6.12.40; 6.13 up to, but not including, 6.15.8; 6.16 | 6.6.100, 6.12.40, 6.15.8 |
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
- HighData or code can be modified at will.
- 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:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 9.8 | Critical | CNA |
| CVSS 3.1 | 7.8 | High | NVD |
Official description
In the Linux kernel, the following vulnerability has been resolved: net: libwx: fix the using of Rx buffer DMA The wx_rx_buffer structure contained two DMA address fields: 'dma' and 'page_dma'. However, only 'page_dma' was actually initialized and used to program the Rx descriptor. But 'dma' was uninitialized and used in some paths. This could lead to undefined behavior, including DMA errors or use-after-free, if the uninitialized 'dma' was used. Althrough such error has not yet occurred, it is worth fixing in the code.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Out-of-bounds Write
The product writes data past the end, or before the beginning, of the intended buffer.
How developers prevent this class of flaw
- Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, many languages that perform their own memory management, such as Java and Perl, are not subject to buffer overflows. Other languages, such as Ada and C#, typically provide overflow protection, but the protection can be disabled by the programmer. Be wary that a language's interface to native code may still be subject to overflows, even if the language itself is theoretically safe.
- Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Examples include the Safe C String Library (SafeStr) by Messier and Viega, and the Strsafe.h library from Microsoft. These libraries provide safer versions of overflow-prone string-handling functions.
- Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking. D3-SFCV (Stack Frame Canary Validation) from D3FEND discusses canary-based detection in detail.
Timeline
- CVE record published.
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Recent Out-of-bounds Write vulnerabilities
- 9.8 Critical severity
- 7.8 High severity
- 7.5 High severity
- 8.8 High severity
- 7.8 High severity
- 7.8 High severity
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