Linux: Out-of-bounds Write
CVE-2024-36895 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 7a54e5052bde582fd0e7677334fe7a5be92e242c, a422089ce42ced73713e5032aad29a9a7cbe9528, 650ae71c80749fc7cb8858c8049f532eaec64410 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 0.23% 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 7a54e5052bde582fd0e7677334fe7a5be92e242c or a422089ce42ced73713e5032aad29a9a7cbe9528 or 650ae71c80749fc7cb8858c8049f532eaec64410, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.6.31 or 6.8.10, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 0df28607c5cb4fe60bba591e9858a8f7ba39aa4a up to, but not including, 7a54e5052bde582fd0e7677334fe7a5be92e242c; 0df28607c5cb4fe60bba591e9858a8f7ba39aa4a up to, but not including, a422089ce42ced73713e5032aad29a9a7cbe9528; 0df28607c5cb4fe60bba591e9858a8f7ba39aa4a up to, but not including, 650ae71c80749fc7cb8858c8049f532eaec64410; 6.3 | 7a54e5052bde582fd0e7677334fe7a5be92e242c, a422089ce42ced73713e5032aad29a9a7cbe9528, 650ae71c80749fc7cb8858c8049f532eaec64410 |
| Linux | Linux Kernel | 6.3 up to, but not including, 6.6.31; 6.7 up to, but not including, 6.8.10; 6.9 | 6.6.31, 6.8.10 |
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.
Official description
In the Linux kernel, the following vulnerability has been resolved: usb: gadget: uvc: use correct buffer size when parsing configfs lists This commit fixes uvc gadget support on 32-bit platforms. Commit 0df28607c5cb ("usb: gadget: uvc: Generalise helper functions for reuse") introduced a helper function __uvcg_iter_item_entries() to aid with parsing lists of items on configfs attributes stores. This function is a generalization of another very similar function, which used a stack-allocated temporary buffer of fixed size for each item in the list and used the sizeof() operator to check for potential buffer overruns. The new function was changed to allocate the now variably sized temp buffer on heap, but wasn't properly updated to also check for max buffer size using the computed size instead of sizeof() operator. As a result, the maximum item size was 7 (plus null terminator) on 64-bit platforms, and 3 on 32-bit ones. While 7 is accidentally just barely enough, 3 is definitely too small for some of UVC configfs attributes. For example, dwFrameInteval, specified in 100ns units, usually has 6-digit item values, e.g. 166666 for 60fps.
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.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Recent Out-of-bounds Write vulnerabilities
- 8.8 High severity
- 8.8 High severity
- 8.8 High severity
- 7.8 High severity
- 7.8 High severity
- 9.8 Critical severity
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