Heap overflow in FUSE_LISTXATTR_CVE-2026-45252

7.5 / 10

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Description

When a fusefs file system implements extended attributes, the kernel may send a FUSE_LISTXATTR message to the userspace daemon to retrieve the list of extended attributes for a given file. The FUSE protocol requires the daemon to return a packed list of NUL-terminated strings. The fusefs kernel module calls strlen() on this daemon-supplied buffer without first verifying that the entire list is NUL-terminated.

If a malicious daemon sends a non-NUL-terminated list, the fusefs kernel module may read beyond the end of one heap-allocated buffer and potentially write beyond the end of a second buffer. A malicious daemon could disclose up to 253 bytes of kernel heap memory, or it could inject up to 250 attacker-controlled bytes into unallocated kernel heap space.

Basic Information

ID CVE-2026-45252

Source freebsd

Published May 21, 2026 at 09:08

Modified May 21, 2026 at 12:29

Affected Product

Vendor FreeBSD

Product FreeBSD

Version 15.0-RELEASE

Affected Versions FreeBSD FreeBSD 15.0-RELEASE
FreeBSD FreeBSD 14.4-RELEASE
FreeBSD FreeBSD 14.3-RELEASE

CWE Classification

CWE-122

References

security.freebsd.org /advisories/FreeBSD-SA-26:20.fusefs.asc

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    "published": "2026-05-21T09:08:00.478Z",
    "modified": "2026-05-21T12:29:42.951Z",
    "type": "cve",
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