Linux Kernel up to 6.12.111/6.18.54/7.2.8/7.3-rc4 sd_zbc sd_zbc_read_zones/sd_zbc_report_zones numeric truncation error

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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9.5$0-$5k2.66-

Summaryinfo

A vulnerability, which was classified as very critical, was found in Linux Kernel up to 6.12.111/6.18.54/7.2.8/7.3-rc4. Impacted is the function sd_zbc_read_zones/sd_zbc_report_zones of the component sd_zbc. The manipulation results in numeric truncation error. This vulnerability is known as CVE-2026-98634. It is possible to launch the attack remotely. No exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as very critical, was found in Linux Kernel up to 6.12.111/6.18.54/7.2.8/7.3-rc4. Affected is the function sd_zbc_read_zones/sd_zbc_report_zones of the component sd_zbc. The manipulation with an unknown input leads to a numeric truncation error vulnerability. CWE is classifying the issue as CWE-197. Truncation errors occur when a primitive is cast to a primitive of a smaller size and data is lost in the conversion. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: scsi: sd_zbc: Reject disks with too many zones sd_zbc_read_zones() computes the number of zones with 64-bit arithmetic and stores the result in the unsigned int nr_zones field of struct zoned_disk_info, silently truncating counts that exceed 32 bits. The truncated count is later used to size per-zone resources, while the device may still report more zones than fit. Moreover, sd_zbc_report_zones() counts the reported zones with a signed int zone_idx, which overflows past INT_MAX. Reject devices reporting more than INT_MAX zones at scan time; such a device is not realistic for any medium that exists today, and accepting it produces inconsistent zone bookkeeping.

The advisory is available at git.kernel.org. This vulnerability is traded as CVE-2026-98634 since 09/25/2026. The exploitability is told to be easy. It is possible to launch the attack 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 10/18/2026).

Upgrading to version 6.12.112, 6.18.55, 7.2.9 or 7.3-rc5 eliminates this vulnerability. Applying the patch d8791ae55d85dfaeafa20ea48365482a0cc5a107/0af16d8be3ec7ff28bb56a0da79c9aed66ac2c3b/3ddf8383b54456f19fd73d3cebed81bd250c7388/b6ec0f79745967c751c85df373062c8d15e45fc4 is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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: Numeric truncation error
CWE: CWE-197 / CWE-189
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 6.12.112/6.18.55/7.2.9/7.3-rc5
Patch: d8791ae55d85dfaeafa20ea48365482a0cc5a107/0af16d8be3ec7ff28bb56a0da79c9aed66ac2c3b/3ddf8383b54456f19fd73d3cebed81bd250c7388/b6ec0f79745967c751c85df373062c8d15e45fc4

Timelineinfo

09/25/2026 CVE reserved
10/18/2026 +23 days Advisory disclosed
10/18/2026 +0 days VulDB entry created
10/18/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-98634 (🔒)
GCVE (CVE): GCVE-0-2026-98634
GCVE (VulDB): GCVE-100-422130

Entryinfo

Created: 10/18/2026 20:34
Changes: 10/18/2026 20:34 (59)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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