The Linux kernel’s mm/mincore subsystem contains a flaw that causes mincore_pte_range() to issue a warning and report pages as non‑resident when swap support is disabled while migration or memory‑failure features are enabled. This occurs because the guard checking for a non‑swap entry runs before the !CONFIG_SWAP check, leading to false warnings and incorrect residency data. The actual residency of the pages is unchanged, but this misreporting can mislead diagnostics, performance monitoring, and tooling that rely on accurate residency information. The weakness is classified as CWE‑393, indicating an incorrect default handling of a condition.

CVE‑2026‑53333 applies to any Linux kernel build that has CONFIG_SWAP disabled and either CONFIG_MIGRATION or CONFIG_MEMORY_FAILURE enabled. All such builds, regardless of distribution, are vulnerable until the patch that moves the swap guard below the non‑swap entry check is applied.

The CVSS score of 5.5 rates the vulnerability as medium. The EPSS score of <1% indicates an extremely low likelihood of exploitation. Because the issue only leads to incorrect residency reporting and does not provide code execution, data exposure, or denial of service, it poses low risk to confidentiality, integrity, or availability. The CVE is not listed in the CISA KEV catalog and no exploitation methods are publicly documented. The likely attack vector is local and requires kernel‑level privileges; it is not an externally exploitable attack.