CVE-2025-39920: debian linux Null Dereference — Fix

Description

In the Linux kernel, the following vulnerability has been resolved: pcmcia: Add error handling for add_interval() in do_validate_mem() In the do_validate_mem(), the call to add_interval() does not handle errors. If kmalloc() fails in add_interval(), it could result in a null pointer being inserted into the linked list, leading to illegal memory access when sub_interval() is called next. This patch adds an error handling for the add_interval(). If add_interval() returns an error, the function will return early with the error code.

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CVSS v3.1 Score

5.5

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-476 CWE-476

Affected Products

Vendor	Product	Versions
linux	linux_kernel	2.6.34 — 5.4.299
linux	linux_kernel	5.5 — 5.10.243
linux	linux_kernel	5.11 — 5.15.192
linux	linux_kernel	5.16 — 6.1.151
linux	linux_kernel	6.2 — 6.6.105
linux	linux_kernel	6.7 — 6.12.46
linux	linux_kernel	6.13 — 6.16.6
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
debian	debian_linux	All

References

Advisories & Patches

https://git.kernel.org/stable/c/06b26e3099207c94b3d1be8565aedc6edc4f0a60 https://git.kernel.org/stable/c/289b58f8ff3198d091074a751d6b8f6827726f3e https://git.kernel.org/stable/c/369bf6e241506583f4ee7593c53b92e5a9f271b4 https://git.kernel.org/stable/c/4a81f78caa53e0633cf311ca1526377d9bff7479 https://git.kernel.org/stable/c/5b60ed401b47897352c520bc724c85aa908dedcc https://git.kernel.org/stable/c/85be7ef8c8e792a414940a38d94565dd48d2f236 https://git.kernel.org/stable/c/8699358b6ac99b8ccc97ed9e6e3669ef8958ef7b https://git.kernel.org/stable/c/ae184024ef31423e5beb44cf4f52999bbcf2fe5b

Other References

https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html

Frequently Asked Questions

What is CVE-2025-39920? +

In the Linux kernel, the following vulnerability has been resolved: pcmcia: Add error handling for add_interval() in do_validate_mem() In the do_validate_mem(), the call to add_interval() does not handle errors. If kmalloc() fails in add_interval(), it could result in a null pointer being inserted into the linked list, leading to illegal memory access when sub_interval() is called next. This patch adds an error handling for the add_interval(). If add_interval() returns an error, the function will return early with the error code. It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2025-39920? +

CVE-2025-39920 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2025-39920? +

CVE-2025-39920 affects products from debian, linux, specifically: debian_linux, linux_kernel. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-39920? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2025-39920