VulnerabilityPublished 6 Oct 2026Updated 19 Oct 2026

CVE-2026-98212: Linux kernel · mmc: hsq: Fix use-after-free in retry work

Affects Linux kernelSource CVE Database V5

Not known to be exploited · fixed in df2eb59fd9eb33663dc1053f5a4ed851e0aa1f67 : patch Linux kernel soon.

Data as of 26 Oct 2026, 13:47 UTC

Severity

High

Rated High by Threat Radar's AI analysis · CVSS not yet scored by NVD

EPSS: 0.2% chance of exploitation in 30 days – higher than 10% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in df2eb59fd9eb33663dc1053f5a4ed851e0aa1f67, c50d6515bffb148c2c12be6d587ec201dfab4c34, 45341b341642c377192c95e4d48e0a859cf85f42 +2

Exploitation evidence

Disclosed: evidence found.
CVE published 6 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected ≥ 6db96e5810e0a6a345b7d78549de7676ae5b2662, < df2eb59fd9eb33663dc1053f5a4ed851e0aa1f67	Fixed in df2eb59fd9eb33663dc1053f5a4ed851e0aa1f67
LinuxLinux	Affected ≥ 6db96e5810e0a6a345b7d78549de7676ae5b2662, < c50d6515bffb148c2c12be6d587ec201dfab4c34	Fixed in c50d6515bffb148c2c12be6d587ec201dfab4c34
LinuxLinux	Affected ≥ 6db96e5810e0a6a345b7d78549de7676ae5b2662, < 45341b341642c377192c95e4d48e0a859cf85f42	Fixed in 45341b341642c377192c95e4d48e0a859cf85f42
LinuxLinux	Affected ≥ 6db96e5810e0a6a345b7d78549de7676ae5b2662, < 8439bf262ce3267bcfee29d3c61605f1731a2271	Fixed in 8439bf262ce3267bcfee29d3c61605f1731a2271
LinuxLinux	Affected ≥ 6db96e5810e0a6a345b7d78549de7676ae5b2662, < 5d132990475f02cfa1debe03d50b479432864ebd	Fixed in 5d132990475f02cfa1debe03d50b479432864ebd
LinuxLinux	Affected =5.8	Fixed in–

AI-suggested

A fix is available and has been applied in specific commits and versions of the Linux kernel. Users should update to a fixed kernel version that includes the patch. No additional mitigation is required once the system is updated, as the patch cancels and drains the retry work properly during driver removal.

Description

A use-after-free vulnerability was identified and fixed in the Linux kernel's MMC subsystem, specifically in the hsq retry work mechanism. The issue arises because retry work is queued but not cancelled during driver removal, allowing work to run after the associated memory has been freed. This could lead to dereferencing freed memory, causing potential instability or crashes. The fix involves using devm_work_autocancel() to properly cancel and drain the retry work before releasing the memory allocation.

Impact

The vulnerability allows use-after-free conditions in the MMC subsystem, which can cause kernel instability, crashes, or potential memory corruption. While no active exploitation is reported, the flaw could be leveraged to disrupt system operation or potentially escalate privileges if combined with other vulnerabilities.

Summary

CVE-2026-98212 addresses a use-after-free vulnerability in the Linux kernel's MMC hsq component. The function mmc_hsq_pump_requests() queues retry_work when request_atomic() returns -EBUSY, but this work is embedded in a devm-allocated mmc_hsq structure that is not cancelled during driver removal. Consequently, pending work may execute after the devm allocation is released, leading to dereferencing of freed pointers hsq->mmc and hsq->mrq. The patch introduces devm_work_autocancel() to cancel and drain retry_work before the devm allocation cleanup, ensuring no new requests can arm the work after mmc_remove_host() stops the host. The vulnerability was discovered via an in-house static analysis tool and affects Linux kernel version 5.8.

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 26 Oct 2026, 12:22 UTC

Technical details

References

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