CVE-2026-45252 | Heap overflow in FUSE_LISTXATTR

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.

Published: 2026-05-21 Last update: 2026-05-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-45252 is rated Low Risk (28.9/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.06%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-45252

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-04 0.02% 0.06% +0.04%
2 2026-05-21 0.02%

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-45252

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:H)
They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.2 4.2 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2026-45252

GitHub Security Advisory for CVE-2026-45252

GHSA-fqrg-fvv5-42g2 · Severity: medium — When a fusefs file system implements extended attributes, the kernel may send a FUSE_LISTXATTR...

Affected software / configurations for CVE-2026-45252

Vendor Product Version Raw CPE
freebsd freebsd 14.3 cpe:2.3:o:freebsd:freebsd:14.3:-:*:*:*:*:*:*
freebsd freebsd 14.3 cpe:2.3:o:freebsd:freebsd:14.3:p1:*:*:*:*:*:*
freebsd freebsd 14.3 cpe:2.3:o:freebsd:freebsd:14.3:p10:*:*:*:*:*:*
freebsd freebsd 14.3 cpe:2.3:o:freebsd:freebsd:14.3:p11:*:*:*:*:*:*
freebsd freebsd 14.3 cpe:2.3:o:freebsd:freebsd:14.3:p12:*:*:*:*:*:*
freebsd freebsd 14.3 cpe:2.3:o:freebsd:freebsd:14.3:p13:*:*:*:*:*:*
freebsd freebsd 14.3 cpe:2.3:o:freebsd:freebsd:14.3:p2:*:*:*:*:*:*
freebsd freebsd 14.3 cpe:2.3:o:freebsd:freebsd:14.3:p3:*:*:*:*:*:*
freebsd freebsd 14.3 cpe:2.3:o:freebsd:freebsd:14.3:p4:*:*:*:*:*:*
freebsd freebsd 14.3 cpe:2.3:o:freebsd:freebsd:14.3:p5:*:*:*:*:*:*
freebsd freebsd 14.3 cpe:2.3:o:freebsd:freebsd:14.3:p6:*:*:*:*:*:*
freebsd freebsd 14.3 cpe:2.3:o:freebsd:freebsd:14.3:p7:*:*:*:*:*:*
freebsd freebsd 14.3 cpe:2.3:o:freebsd:freebsd:14.3:p8:*:*:*:*:*:*
freebsd freebsd 14.3 cpe:2.3:o:freebsd:freebsd:14.3:p9:*:*:*:*:*:*
freebsd freebsd 14.4 cpe:2.3:o:freebsd:freebsd:14.4:-:*:*:*:*:*:*
freebsd freebsd 14.4 cpe:2.3:o:freebsd:freebsd:14.4:p1:*:*:*:*:*:*
freebsd freebsd 14.4 cpe:2.3:o:freebsd:freebsd:14.4:p2:*:*:*:*:*:*
freebsd freebsd 14.4 cpe:2.3:o:freebsd:freebsd:14.4:p3:*:*:*:*:*:*
freebsd freebsd 14.4 cpe:2.3:o:freebsd:freebsd:14.4:p4:*:*:*:*:*:*
freebsd freebsd 14.4 cpe:2.3:o:freebsd:freebsd:14.4:rc1:*:*:*:*:*:*
freebsd freebsd 15.0 cpe:2.3:o:freebsd:freebsd:15.0:-:*:*:*:*:*:*
freebsd freebsd 15.0 cpe:2.3:o:freebsd:freebsd:15.0:p1:*:*:*:*:*:*
freebsd freebsd 15.0 cpe:2.3:o:freebsd:freebsd:15.0:p2:*:*:*:*:*:*
freebsd freebsd 15.0 cpe:2.3:o:freebsd:freebsd:15.0:p3:*:*:*:*:*:*
freebsd freebsd 15.0 cpe:2.3:o:freebsd:freebsd:15.0:p4:*:*:*:*:*:*
freebsd freebsd 15.0 cpe:2.3:o:freebsd:freebsd:15.0:p5:*:*:*:*:*:*
freebsd freebsd 15.0 cpe:2.3:o:freebsd:freebsd:15.0:p6:*:*:*:*:*:*
freebsd freebsd 15.0 cpe:2.3:o:freebsd:freebsd:15.0:p7:*:*:*:*:*:*
freebsd freebsd 15.0 cpe:2.3:o:freebsd:freebsd:15.0:p8:*:*:*:*:*:*

References for CVE-2026-45252

cvelogic Threat Intelligence