CVE-2021-35039
kernel: allows loading unsigned kernel modules via init_module syscall
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · July 6, 2021
Updated · June 28, 2026
Description
A flaw incorrect handle of boot param module.sig_enforce=1 in the Linux kernel modules sign verification functionality was found in the way user boot with this param enabled and both if kernel compiled with param CONFIG_MODULE_SIG unset, then user still can load unsigned module even param module.sig_enforce pretending to be enabled. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
Statement
This issue is rated as having a Moderate impact because of the privileges required for loading malicious unsigned kernel module.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
No mitigation is specified in collected source.
CVSS / CWE
CVSS 3.1 · 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE-347 · Improper Verification of Cryptographic Signature