Linux Kernel up to 6.12.91/6.18.33/7.0.10 block blk-mq.c blk_insert_cloned_request stack-based overflow

CVSS Meta Temp Score
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CTI Interest Score
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6.0$0-$5k6.22

Summaryinfo

A vulnerability labeled as critical has been found in Linux Kernel up to 6.12.91/6.18.33/7.0.10. Affected by this issue is the function blk_insert_cloned_request of the file blk-mq.c of the component block. Executing a manipulation can lead to stack-based overflow. This vulnerability is handled as CVE-2026-64232. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.12.91/6.18.33/7.0.10. It has been declared as critical. This vulnerability affects the function blk_insert_cloned_request of the file blk-mq.c of the component block. The manipulation with an unknown input leads to a stack-based overflow vulnerability. The CWE definition for the vulnerability is CWE-121. A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function). As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: block: recompute nr_integrity_segments in blk_insert_cloned_request blk_insert_cloned_request() already recomputes nr_phys_segments against the bottom queue, because "the queue settings related to segment counting may differ from the original queue." The exact same reasoning applies to integrity segments: a stacked driver's underlying queue can have tighter virt_boundary_mask, seg_boundary_mask, or max_segment_size than the top queue, in which case blk_rq_count_integrity_sg() against the bottom queue produces a different count than the cached rq->nr_integrity_segments inherited from the source request by blk_rq_prep_clone(). When the cached count is lower than the bottom queue's actual count, blk_rq_map_integrity_sg() trips BUG_ON(segments > rq->nr_integrity_segments); on dispatch. The same families of stacked setups that motivated the existing nr_phys_segments recompute -- dm-multipath fanning out to nvme-rdma in particular -- can produce this. Mirror the nr_phys_segments handling: when the request carries integrity, recompute nr_integrity_segments against the bottom queue and reject the request if it exceeds the bottom queue's max_integrity_segments. blk_rq_count_integrity_sg() and queue_max_integrity_segments() are both already available via <linux/blk-integrity.h>, which blk-mq.c includes. This closes a latent gap in the stacking contract and brings the integrity-segment accounting in line with the existing phys-segment accounting.

The advisory is available at git.kernel.org. This vulnerability was named CVE-2026-64232 since 07/19/2026. The exploitation appears to be easy. The attack can be initiated remotely. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 07/24/2026).

Upgrading to version 6.12.92, 6.18.34 or 7.0.11 eliminates this vulnerability. Applying the patch 53a01bcc0242590eda4c452a5bd996f62457113b/0943f81e1b3176f27dbaf6db268fc69d8a94f0ba/42929c98d044f126508baf54a65b0f87f932fa75/2c6e6a18a37b905cb584eb0dda3ae482162a81ca is able to eliminate this problem.

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Productinfo

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
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: Stack-based overflow
CWE: CWE-121 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
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 6.12.92/6.18.34/7.0.11
Patch: 53a01bcc0242590eda4c452a5bd996f62457113b/0943f81e1b3176f27dbaf6db268fc69d8a94f0ba/42929c98d044f126508baf54a65b0f87f932fa75/2c6e6a18a37b905cb584eb0dda3ae482162a81ca

Timelineinfo

07/19/2026 CVE reserved
07/24/2026 +5 days Advisory disclosed
07/24/2026 +0 days VulDB entry created
07/24/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-64232 (🔒)
GCVE (CVE): GCVE-0-2026-64232
GCVE (VulDB): GCVE-100-382966

Entryinfo

Created: 07/24/2026 18:39
Changes: 07/24/2026 18:39 (60)
Complete: 🔍
Cache ID: 216::103

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