CVE-2026-64397

NameCVE-2026-64397
DescriptionIn the Linux kernel, the following vulnerability has been resolved: ksmbd: serialize QUERY_DIRECTORY requests per file smb2_query_dir() stores a pointer to its stack-allocated private data in the ksmbd_file readdir_data. Concurrent QUERY_DIRECTORY requests using the same file handle can overwrite this pointer while an iterate_dir() callback is still using it, resulting in a stack use-after-free. Add a per-file mutex and hold it while accessing the shared directory enumeration state. The lock covers scan restart, dot entry state, readdir_data setup and iteration, and response construction. This prevents another request from replacing readdir_data.private before the current request has finished using it and also serializes the shared file position.
SourceCVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
ReferencesDLA-4720-1, DLA-4723-1, DLA-4724-1

Vulnerable and fixed packages

The table below lists information on source packages.

Source PackageReleaseVersionStatus
linux (PTS)bullseye5.10.223-1fixed
bullseye (security)5.10.262-1fixed
bookworm6.1.176-1vulnerable
bookworm (security)6.1.180-1fixed
trixie6.12.94-1vulnerable
trixie (security)6.12.101-1fixed
forky7.1.7-1fixed
sid7.1.8-1fixed
linux-6.1 (PTS)bullseye (security)6.1.180-1~deb11u1fixed
linux-6.12 (PTS)bookworm (security)6.12.100-1~deb12u1fixed

The information below is based on the following data on fixed versions.

PackageTypeReleaseFixed VersionUrgencyOriginDebian Bugs
linuxsourcebullseye(not affected)
linuxsourcebookworm6.1.180-1DLA-4720-1
linuxsourcetrixie6.12.96-1
linuxsource(unstable)7.1.4-1
linux-6.1sourcebullseye6.1.180-1~deb11u1DLA-4723-1
linux-6.12sourcebookworm6.12.100-1~deb12u1DLA-4724-1

Notes

[bullseye] - linux <not-affected> (Vulnerable code not present)
https://git.kernel.org/linus/be6d26bf27499977c746abc163659915082348d8 (7.2-rc1)

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