Improper control of a resource through its lifetime in Linux kernel - CVE-2026-98975

Vulnerability details

The vulnerability allows a local user to corrupt data in files that share filesystem blocks.

The vulnerability exists due to improper management of reflink flags in the XFS mapping-exchange and extent-swap paths when exchanging mappings between files that retain shared blocks. A local user can perform an affected exchange and subsequently write to a shared block whose inode has lost its reflink flag, causing an in-place write instead of copy-on-write to corrupt another file sharing that block.

Affected software

How to mitigate CVE-2026-98975

External References

• https://git.kernel.org/stable/c/1fa2f3a7ef7ee0f2503a4b0afe24bc8c9d0820be
• https://git.kernel.org/stable/c/4756c94260e69ce42612b8220c3614f02f7a11d5
• https://git.kernel.org/stable/c/7d3b9b2c9dc57f93f36c716ab752548cb4db9900
• https://git.kernel.org/stable/c/d84d6c1a7f1e2de9e601703a326a4c1b7b421943

Related Security Bulletins

• Improper control of a resource through its lifetime in Linux kernel xfs
• Debian update for linux