CVE-2026-45948 ext4: fix memory leak in ext4_ext_shift_extents()

What is CVE-2026-45948?

CVE-2026-45948 is a medium-severity denial of service vulnerability in Linux kernel, published on 27 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In the Linux kernel, the following vulnerability has been resolved:

ext4: fix memory leak in ext4_ext_shift_extents()

In ext4_ext_shift_extents(), if the extent is NULL in the while loop, the function returns immediately without releasing the path obtained via ext4_find_extent(), leading to a memory leak.

Fix this by jumping to the out label to ensure the path is properly released.

Weakness: CWE-401

Which versions are affected by CVE-2026-45948?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2026-45948?

Apply the vendor's patch.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2026-45948 being exploited?

There is no known exploitation of CVE-2026-45948 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BELL-CVE-2026-45948, DEBIAN-CVE-2026-45948, GHSA-gvfq-9hrf-2536, ROOT-OS-UBUNTU-2204-CVE-2026-45948, ROOT-OS-UBUNTU-2404-CVE-2026-45948, UBUNTU-CVE-2026-45948.