Linux Kernel up to 6.18.58/7.2.12 s390/pci report_error_write length out-of-bounds

CVSS Meta Temp Score
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CTI Interest Score
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1.9$0-$5k1.71

Summaryinfo

A vulnerability has been found in Linux Kernel up to 6.18.58/7.2.12 and classified as problematic. The impacted element is the function report_error_write of the component s390/pci. This manipulation of the argument length causes out-of-bounds. This vulnerability is registered as CVE-2026-99124. The attack needs to be launched locally. No exploit is available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.18.58/7.2.12. It has been declared as problematic. Affected by this vulnerability is the function report_error_write of the component s390/pci. The manipulation of the argument length with an unknown input leads to a out-of-bounds vulnerability. The CWE definition for the vulnerability is CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: s390/pci: Fix leak of uninitialized kernel data in SCLP report While report_error_write() checks that the provided buffer is at least as large as the header struct, but not that it is large enough to contain the report with the length claimed by report->length. If user-space provides a short buffer, meaning a larger report->length than the actually written payload, up to around 4K of kernel data from past the kmalloc(len + 1) sized buffer allocated in kernfs_fop_write_iter() will leak into the SCLP report. However, as the entity processing the SCLP is privileged and able to access at least the page including the report, this does not leak data that entity could not access but it is still an out of bounds read and a malformed error report that should be rejected.

The advisory is shared at git.kernel.org. This vulnerability is known as CVE-2026-99124 since 09/25/2026. The exploitation appears to be easy. An attack has to be approached locally. The exploitation requires an enhanced level of successful authentication. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available.

Upgrading to version 6.18.59 or 7.2.13 eliminates this vulnerability. Applying the patch ba5001db9bb23ff7d2ea328c405c287ffb07786f/126a7c227d8543e13903dd5622640c1f0fcc5a16/8ac60ae2a307a50b599bf5d300b448d638f3ba29 is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

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Vendor

Name

Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 2.0
VulDB Meta Temp Score: 1.9

VulDB Base Score: 2.0
VulDB Temp Score: 1.9
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: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

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 6.18.59/7.2.13
Patch: ba5001db9bb23ff7d2ea328c405c287ffb07786f/126a7c227d8543e13903dd5622640c1f0fcc5a16/8ac60ae2a307a50b599bf5d300b448d638f3ba29

Timelineinfo

09/25/2026 CVE reserved
10/28/2026 +33 days Advisory disclosed
10/28/2026 +0 days VulDB entry created
10/28/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-99124 (🔒)
GCVE (CVE): GCVE-0-2026-99124
GCVE (VulDB): GCVE-100-427885

Entryinfo

Created: 10/28/2026 12:42
Changes: 10/28/2026 12:42 (60)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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