CVE-2026-43484 | mmc: core: Avoid bitfield RMW for claim/retune flags

In the Linux kernel, the following vulnerability has been resolved: mmc: core: Avoid bitfield RMW for claim/retune flags Move claimed and retune control flags out of the bitfield word to avoid unrelated RMW side effects in asynchronous contexts. The host->claimed bit shared a word with retune flags. Writes to claimed in __mmc_claim_host() or retune_now in mmc_mq_queue_rq() can overwrite other bits when concurrent updates happen in other contexts, triggering spurious WARN_ON(!host->claimed). Convert claimed, can_retune, retune_now and retune_paused to bool to remove shared-word coupling.

Published: 2026-05-13 Last update: 2026-05-13 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Conclusion & alert: CVE-2026-43484 is rated Low Risk (7.1/100): low exploitation likelihood (EPSS 0.02%). Mandatory action: Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-43484

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-14 0.02%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-43484

CVSS metrics for this CVE.

No CVSS data in dataset for this CVE.

Weakness enumeration for CVE-2026-43484

GitHub Security Advisory for CVE-2026-43484

GHSA-42p4-9577-4wfh · Severity: unknown — In the Linux kernel, the following vulnerability has been resolved: mmc: core: Avoid bitfield...

OS Trackers for CVE-2026-43484

vendor priority summary link
debian not yet assigned CVE-2026-43484 not yet assigned priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 4, open 1. https://security-tracker.debian.org/tracker/CVE-2026-43484
redhat low https://access.redhat.com/security/cve/CVE-2026-43484
suse medium CVE-2026-43484 severity moderate: SUSE including 7 source package names (kernel-default, kernel-default-base, …), 13 product×package rows across 3 product lines (SUSE Linux Enterprise Server 11 SP4 LTSS EXTREME CORE, SUSE Linux Enterprise Server 12 SP4-LTSS, SUSE Linux Enterprise Server Teradata 12 SP3): Known Not Affected 13. https://www.suse.com/security/cve/CVE-2026-43484/
ubuntu medium CVE-2026-43484 medium priority: Ubuntu including 161 source packages (linux, linux-allwinner-5.19, …), 1449 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): DNE 1048, ignored 170, needed 126, released 83, not-affected 17, needs-triage 5. https://ubuntu.com/security/CVE-2026-43484

Affected software / configurations for CVE-2026-43484

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-43484

cvelogic Threat Intelligence