CVE-2026-90211
kernel: bpf, s390: Clear fetch destination on faulting arena atomic
Severity
LowRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · September 17, 2026
Updated · October 14, 2026
Description
A flaw was found in the Linux kernel's BPF (Berkeley Packet Filter) component, specifically affecting the s390 architecture. When a read-modify-write atomic operation with BPF_FETCH faults over an unmapped memory region, a register may not be properly cleared. This can lead to the program resuming with an uninitialized register value, potentially disclosing sensitive information or causing unpredictable behavior.
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 · 6.1CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H
CWE-908 · Use of Uninitialized Resource