CVE Catalog

CVE-2026-74392

Low risk· EPSS 5%
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.16%

5th percentile - higher than 5% of all known CVEs

Summary

In the Linux kernel, dm_poll_bio() passed polling flags unchanged to clones, which could cause long spinning and RCU CPU stall. The fix forces one-shot polling for target bios.

Risk Assessment

The vulnerability may lead to system hang (RCU stall) or significant performance degradation.

Recommendation

Apply the Linux kernel update containing the fix for CVE-2026-74392.

Other vulnerabilities in Linux kernel

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Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: dm: limit target bio polling to one shot dm_poll_bio() is the ->poll_bio() callback for a stacked dm device. The caller only knows about the dm queue, so it may decide to do a spinning poll if it thinks a single queue is being polled. Passing those flags unchanged to the mapped clone lets blk_mq_poll() spin on a target queue from inside dm_poll_bio(). With io_uring IOPOLL on a dm-stripe target this can keep a task in dm_poll_bio() -> bio_poll() -> blk_mq_poll() long enough to trigger an RCU CPU stall, before io_uring gets back to io_iopoll_check() and its need_resched() check. Keep dm's ->poll_bio() bounded by forcing one-shot polling for target bios. The caller can invoke dm_poll_bio() again if it wants to keep polling, and it also gets a chance to reap completions or reschedule between passes.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS