Linux Kernel up to 7.3-rc3 MMC Core mmc_free_host use after free

CVSS Meta Temp Score
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CTI Interest Score
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9.5$5k-$25k0.00

Summaryinfo

A vulnerability identified as very critical has been detected in Linux Kernel up to 7.3-rc3. This impacts the function mmc_free_host of the component MMC Core. This manipulation causes use after free. This vulnerability is registered as CVE-2026-98213. Remote exploitation of the attack is possible. No exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 7.3-rc3. It has been declared as very critical. Affected by this vulnerability is the function mmc_free_host of the component MMC Core. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: mmc: core: Cancel SDIO IRQ work before freeing host A host controller that uses sdio_signal_irq() schedules host->sdio_irq_work from its interrupt handler. That work is only cancelled on the suspend path (mmc_sdio_suspend()), not on the remove/free path, so a worker armed just before the controller freed its IRQ can run after mmc_host_classdev_release() has freed the host and dereference it through container_of(). Cancel host->sdio_irq_work in mmc_free_host(), like the existing host->detect drain added by commit 1036f69e2513 ("mmc: core: Cancel delayed work before releasing host"). This issue was found by an in-house static analysis tool.

It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2026-98213 since 09/25/2026. The exploitation appears to be easy. The attack can be launched remotely. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 10/06/2026).

Upgrading to version 6.1.189, 6.6.158, 6.12.112, 6.18.54, 7.2.8 or 7.3-rc4 eliminates this vulnerability. Applying the patch bae1cf4f9902b2065bd78b759c7fe6312855f05e/0bf3d168a2cc20b120d6b50f0a8ac5b40ff4d589/1d6e7315ee1c992b4ca42c9b11c5ed0e925a00e0/4553b5004eca9c9eae29a421f1a9c4d5db2c9114/2a863458828ade0671c2bc2e469bbd7f2340eb03/6feadbecdae60a6324c967f3b1493741083793a3 is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.9
VulDB Meta Temp Score: 9.5

VulDB Base Score: 9.9
VulDB Temp Score: 9.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.1.189/6.6.158/6.12.112/6.18.54/7.2.8/7.3-rc4
Patch: bae1cf4f9902b2065bd78b759c7fe6312855f05e/0bf3d168a2cc20b120d6b50f0a8ac5b40ff4d589/1d6e7315ee1c992b4ca42c9b11c5ed0e925a00e0/4553b5004eca9c9eae29a421f1a9c4d5db2c9114/2a863458828ade0671c2bc2e469bbd7f2340eb03/6feadbecdae60a6324c967f3b1493741083793a3

Timelineinfo

09/25/2026 CVE reserved
10/06/2026 +11 days Advisory disclosed
10/06/2026 +0 days VulDB entry created
10/06/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CNA: Linux
CVE: CVE-2026-98213 (🔒)

GCVE (CVE): GCVE-0-2026-98213
GCVE (VulDB): GCVE-100-414115

Entryinfo

Created: 10/06/2026 12:53
Changes: 10/06/2026 12:53 (59)
Complete: 🔍
Cache ID: 216::103

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