CVE-2025-40323
7.8 · HIGHOverview
CVE-2025-40323 is a high-severity vulnerability. It was published on December 8, 2025 and has a CVSS 3.1 base score of 7.8 (HIGH).
This vulnerability has a CVSS 3.1 base score of 7.8, rated HIGH. It requires local or adjacent network access to exploit. Some level of privileges is required for exploitation.
Technical Description
In the Linux kernel, the following vulnerability has been resolved:
fbcon: Set fb_display[i]->mode to NULL when the mode is released
Recently, we discovered the following issue through syzkaller:
BUG: KASAN: slab-use-after-free in fb_mode_is_equal+0x285/0x2f0
Read of size 4 at addr ff11000001b3c69c by task syz.xxx
...
Call Trace:
<TASK>
dump_stack_lvl+0xab/0xe0
print_address_description.constprop.0+0x2c/0x390
print_report+0xb9/0x280
kasan_report+0xb8/0xf0
fb_mode_is_equal+0x285/0x2f0
fbcon_mode_deleted+0x129/0x180
fb_set_var+0xe7f/0x11d0
do_fb_ioctl+0x6a0/0x750
fb_ioctl+0xe0/0x140
__x64_sys_ioctl+0x193/0x210
do_syscall_64+0x5f/0x9c0
entry_SYSCALL_64_after_hwframe+0x76/0x7e
Based on experimentation and analysis, during framebuffer unregistration,
only the memory of fb_info->modelist is freed, without setting the
corresponding fb_display[i]->mode to NULL for the freed modes. This leads
to UAF issues during subsequent accesses. Here's an example of reproduction
steps:
1.
Remediation
Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
References
Frequently Asked Questions
What is CVE-2025-40323?
CVE-2025-40323 is a high-severity vulnerability. It was published on December 8, 2025 and has a CVSS 3.1 base score of 7.8 (HIGH).
How severe is CVE-2025-40323?
This vulnerability has a CVSS 3.1 base score of 7.8, rated HIGH. It requires local or adjacent network access to exploit. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2025-40323?
Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2025-40323?
CyberStrike's AI-powered security agents can automatically detect CVE-2025-40323 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
Automated penetration testing that runs continuously, not just quarterly.
AI-driven PR review catches vulnerable dependencies before they ship.
Browser-based exploitation validates findings with real proof-of-concept.
Related HIGH CVEs from 2025
View all →HCL MyXalytics is affected by out-of-band resource load (HTTP) vulnerability. An attacker can deplo
The NextEPC MME <= 1.0.1 (fixed in commit a8492c9c5bc0a66c6999cb5a263545b32a4109df) contains a stack
A flaw was found in the Red Hat Advanced Cluster Security (RHACS) portal. When rendering a table vie
A Stored Cross-Site Scripting (XSS) vulnerability exists in the chat file upload functionality of op
A: Improper Neutralization of Input During Web Page Generation vulnerability in SUSE rancher allows
Mbed TLS before 3.6.4 allows a use-after-free in certain situations of applications that are develop
In iperf before 3.19.1, net.c has a buffer overflow when --skip-rx-copy is used (for MSG_TRUNC in re
Missing authorization in Ivanti Connect Secure before 22.7R2.9 or 22.8R2, Ivanti Policy Secure befor
Memory corruptions can be remotely triggered in the Control-M/Agent when SSL/TLS communication is co
Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerab
Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerab
An issue in Orban Optimod 5950, Optimod 5950HD, Optimod 5750, Optimod 5750HD, Optimod Trio Optimod v