CVE Catalog

CVE-2026-98921

Unknown
Published: Translated: NVD NIST

Summary

In the overlayfs filesystem, ovl_do_mkdir() printed the input dentry with %pd after calling vfs_mkdir(), which may free or replace the dentry, leading to a use-after-free when CONFIG_OVERLAY_FS_DEBUG is enabled. The fix prints the dentry before the call and only the result afterward.

Risk Assessment

With overlayfs debugging enabled, a local user can trigger a kernel use-after-free, risking system crash or potential privilege escalation.

Recommendation

Update the Linux kernel to a patched version. If possible, disable CONFIG_OVERLAY_FS_DEBUG until the update is applied.

Other vulnerabilities in Linux kernel

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Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: ovl: fix UAF in ovl_do_mkdir() debug print ovl_do_mkdir() prints the input dentry with %pd after vfs_mkdir(). Since commit fe497f0759e0 ("VFS: change vfs_mkdir() to unlock on failure."), vfs_mkdir() calls end_creating() on the input dentry on failure and may replace it on success, so the post-call %pd can use-after-free the dentry when CONFIG_OVERLAY_FS_DEBUG is enabled. Print the dentry before the call and only the result afterward.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS