### [CVE-2025-38685](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2025-38685)
![](https://img.shields.io/static/v1?label=Product&message=Linux&color=blue)
![](https://img.shields.io/static/v1?label=Version&message=&color=brightgreen)
![](https://img.shields.io/static/v1?label=Version&message=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2%20&color=brightgreen)
![](https://img.shields.io/static/v1?label=Vulnerability&message=n%2Fa&color=blue)

### Description

In the Linux kernel, the following vulnerability has been resolved:fbdev: Fix vmalloc out-of-bounds write in fast_imageblitThis issue triggers when a userspace program does an ioctlFBIOPUT_CON2FBMAP by passing console number and frame buffer number.Ideally this maps console to frame buffer and updates the screen ifconsole is visible.As part of mapping it has to do resize of console according to framebuffer info. if this resize fails and returns from vc_do_resize() andcontinues further. At this point console and new frame buffer are mappedand sets display vars. Despite failure still it continue to proceedupdating the screen at later stages where vc_data is related to previousframe buffer and frame buffer info and display vars are mapped to newframe buffer and eventully leading to out-of-bounds write infast_imageblit(). This bheviour is excepted only when fg_console isequal to requested console which is a visible console and updates screenwith invalid struct references in fbcon_putcs().

### POC

#### Reference
No PoCs from references.

#### Github
- https://github.com/w4zu/Debian_security