Unknown

CVE-2026-68478 — memstick: ms_block: reject a card that reports too many blocks

In the Linux kernel, the following vulnerability has been resolved: memstick: ms_block: reject a card that reports too many blocks msb_ftl_initialize() computes the zone count from the card block count with no bound: msb->zone_count = msb->block_count / MS_BLOCKS_IN_ZONE; ... for (i = 0; i < msb->zone_count; i++) msb->free_block_count[i] = MS_BLOCKS_IN_ZONE; msb->block_count is a card value. msb_read_boot_blocks() reads number_of_blocks from the card boot page and byte swaps it. free_block_count is a fixed int[MS_MAX_ZONES]. MS_MAX_ZONES is 16, so the valid indices are 0 to 15. The init loop above indexes it by zone_count. msb_mark_block_used() and msb_mark_block_unused() index it by pba / MS_BLOCKS_IN_ZONE, for pba up to block_count - 1. A card may report up to 65535 blocks. A block_count above 8192 (MS_MAX_ZONES * MS_BLOCKS_IN_ZONE) lets the pba index reach 16. That writes past free_block_count[] and corrupts struct msb_data. A larger count runs the init loop past the end too. A real Memory Stick has at most 16 zones. So it has at most 8192 blocks. msb_ftl_initialize() now rejects a card that reports more than MS_MAX_ZONES * MS_BLOCKS_IN_ZONE blocks.

Published Aug 15, 2026 · Updated Oct 15, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: Linux

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.2% (30-day exploitation probability)+2

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.22%

ahead of 13% of scored CVEs · Oct 30, 2026

Affects

Linux

CVSS base

—

Score not published yet.

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
No fix documented in the sources: reduce exposure and monitor the vendor advisory.
Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Linux	Linux	≥ 0ab30494bc4f3bc1ea4659b7c5d97c5218554a63 and < a4b9961efe8640f50800811b4a2b2046b3dc2ccc≥ 0ab30494bc4f3bc1ea4659b7c5d97c5218554a63 and < 8937b11f1c3896e066c3fb07387ba17bc8c50b8a≥ 0ab30494bc4f3bc1ea4659b7c5d97c5218554a63 and < f1c675ecf6e5ad02722f0019f729d8bb588d502e≥ 0ab30494bc4f3bc1ea4659b7c5d97c5218554a63 and < d5db3439ee8d1c165a09a47e984c4ba508c130df≥ 0ab30494bc4f3bc1ea4659b7c5d97c5218554a63 and < b86666ac4009a252501cc17242582a7ec9ed976e≥ 0ab30494bc4f3bc1ea4659b7c5d97c5218554a63 and < 39151f0708c84221e94cdd6aa070aba5d7cb1c01≥ 0ab30494bc4f3bc1ea4659b7c5d97c5218554a63 and < 47f0c7d856c67c9935546d2644f18c0d0131b449≥ 0ab30494bc4f3bc1ea4659b7c5d97c5218554a63 and < 718178f524b98bc920d74bc771aed823c8b81425 and 1 more version 3.12	Vulnerable	CVE Program (cve.org) e CISA ADP

EPSS over time FIRST

Oct 15, 2026 → Oct 30, 2026 · 15 reading(s) · max 0.22%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Not enough vector or weakness data: use the affected application’s logs as a starting point.

application logs

Timeline

What happened to this CVE, newest first.

2026
Record published
Oct 15, 2026
Affected products added · linux/linux
Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
Source status changed · → Received
Oct 15, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 15, 2026 · NIST National Vulnerability Database
CVE published
Aug 15, 2026 · Linux

Source activity

Repeated readings are counted rather than listed.

1× Official description updated · Oct 15, 2026 – Oct 15, 2026

References

8 on the record

git.kernel.org/stable/c/b86666ac4009a252501cc17242582a7ec9ed976e
NIST National Vulnerability Database
git.kernel.org/stable/c/8937b11f1c3896e066c3fb07387ba17bc8c50b8a
NIST National Vulnerability Database
git.kernel.org/stable/c/d5db3439ee8d1c165a09a47e984c4ba508c130df
NIST National Vulnerability Database
git.kernel.org/stable/c/39151f0708c84221e94cdd6aa070aba5d7cb1c01
NIST National Vulnerability Database
git.kernel.org/stable/c/47f0c7d856c67c9935546d2644f18c0d0131b449
NIST National Vulnerability Database
git.kernel.org/stable/c/718178f524b98bc920d74bc771aed823c8b81425
NIST National Vulnerability Database
git.kernel.org/stable/c/a4b9961efe8640f50800811b4a2b2046b3dc2ccc
NIST National Vulnerability Database
git.kernel.org/stable/c/f1c675ecf6e5ad02722f0019f729d8bb588d502e
NIST National Vulnerability Database

Elsewhere on this site

Linux
every CVE for this vendor

Related CVEs (same products)

Unknown CVE-2026-99216 Drivers: hv: Don't reset VMBus connection state on error/exit paths 2d
Unknown CVE-2026-99215 power: supply: core: prevent unregistering a power supply while a callback runs 2d
Unknown CVE-2026-99207 scsi: target: Disable interrupts while holding delayed_cmd_lock 2d
Unknown CVE-2026-99208 drm/xe/oa: Zero OA buffer at allocation 2d
Unknown CVE-2026-99209 drm/xe: skip eviction of a BO with no resource 2d
Unknown CVE-2026-99210 accel/rocket: clear rdev on device init failure 2d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No CVSS score published by NVD, the CNA, CISA or GitHub so far.
No fixed version, patch or mitigation documented.
No CISA SSVC assessment.
No CWE classification.
No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-68478 is "memstick: ms_block: reject a card that reports too many blocks", rated Unknown. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.22% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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