CVE-2023-39191: Kernel: ebpf: insufficient stack type checks in dynptr

Severity: high (CVSS 8.2 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-10-04 · updated 2026-06-17
Weakness: CWE-20

Description

An improper input validation flaw was found in the eBPF subsystem in the Linux kernel. The issue occurs due to a lack of proper validation of dynamic pointers within user-supplied eBPF programs prior to executing them. This may allow an attacker with CAP_BPF privileges to escalate privileges and execute arbitrary code in the context of the kernel.

Affected products

Fedoraproject Fedora: 38
Linux kernel: from 5.19 before 6.3 — fixed in 6.3
Red Hat Enterprise Linux: 9.0

How to fix

Upgrade to a fixed version: Linux kernel 6.3. Check the vendor advisory for mitigations.

References

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