SECURELYN

CVE-2026-97359

HFS2 version 2.4.0 and earlier contains a template injection vulnerability in the multipart upload handler that allows unauthenticated attackers to achieve remote code execution by embedding malicious template syntax in a filename. Attackers can craft a filename containing a closing template quoting sequence followed by an exec macro, which bypasses the authorization check in the dispatcher to execute arbitrary commands on the underlying host system.

Scores

10.0
CVSS 10.0 out of 10, critical severity.
0.8%
EPSS 0.8% chance of exploitation in the next 30 days.

The facts

Published
24 September 2026
Last changed
29 September 2026
NVD status
Deferred
Severity
Critical, CVSS 10.0 out of 10 (version 4.0)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R…
Weakness
Known exploited
Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
EPSS
0.8% chance of exploitation activity in the next 30 days (percentile 55).

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References