s390/dasd: Do not complete a failed ESE read as successful (CVE-2026-89458) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-89458

s390/dasd: Do not complete a failed ESE read as successful

Answer in brief

CVE-2026-89458 records a Unknown severity vulnerability in s390/dasd: Do not complete a failed ESE read as successful. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 11, 2026Updated Sep 11, 2026Source checked Sep 11, 2026First seen by HOL Sep 11, 2026Material review Sep 11, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Linux/Linuxgeneric	>=5e6bdd37c5526ef01326df5dabb93011ee89237e <c9adf8399732306dfc97b3adb4778038743e3f5e \|\| >=5e6bdd37c5526ef01326df5dabb93011ee89237e <52b331c99baac653ca794bd8487c8ec4de8db203 \|\| >=5e6bdd37c5526ef01326df5dabb93011ee89237e <b0d94dd6e82df396e2254c8b0f25eff7d19c2e7f \|\| >=5e6bdd37c5526ef01326df5dabb93011ee89237e <cddb447c62466f3076938ce120028d7b591f9f37 \|\| fbbacd0dcbc3ae9398c569dbea96ae4b5ad97e04 \|\| 5f7c9989f11305aaa43e0f4378f4f070022a9f2b \|\| >=5.4.26 <5.5 \|\| >=5.5.10 <5.6	c9adf8399732306dfc97b3adb4778038743e3f5e, 52b331c99baac653ca794bd8487c8ec4de8db203, b0d94dd6e82df396e2254c8b0f25eff7d19c2e7f, cddb447c62466f3076938ce120028d7b591f9f37, 5.5, 5.6
Linux/Linuxgeneric	5.6	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to c9adf8399732306dfc97b3adb4778038743e3f5e if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 11, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 11, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 11, 2026

Sources and claim methodology

Upstream source description

In the Linux kernel, the following vulnerability has been resolved: s390/dasd: Do not complete a failed ESE read as successful dasd_int_handler() completes an NRF read of an unallocated ESE track by calling ese_read() and unconditionally marking the request DASD_CQR_SUCCESS. dasd_eckd_ese_read() can return an error before it has zeroed the destination buffer: a failed sense-data parse or a current track outside the requested range both return early, leaving the destination pages untouched. The request is still completed successfully, so the block layer is handed stale / uninitialized memory instead of zeros. Check the ese_read() return value and fail the request through the normal error path instead of forcing DASD_CQR_SUCCESS.

Quoted source text, attributed separately from HOL analysis.