Summary
In the Linux kernel, the following vulnerability has been resolved: dm: limit swapping tables...
In the Linux kernel, the following vulnerability has been resolved:
dm: limit swapping tables for devices with zone write plugs
dm_revalidate_zones() only allowed new or previously unzoned devices to
call blk_revalidate_disk_zones(). If the device was already zoned,
disk->nr_zones would always equal md->nr_zones, so dm_revalidate_zones()
returned without doing any work. This would make the zoned settings for
the device not match the new table. If the device had zone write plug
resources, it could run into errors like bdev_zone_is_seq() reading
invalid memory because disk->conv_zones_bitmap was the wrong size.
If the device doesn't have any zone write plug resources, calling
blk_revalidate_disk_zones() will always correctly update device. If
blk_revalidate_disk_zones() fails, it can still overwrite or clear the
current disk->nr_zones value. In this case, DM must restore the previous
value of disk->nr_zones, so that the zoned settings will continue to
match the previous value that it fell back to.
If the device already has zone write plug resources,
blk_revalidate_disk_zones() will not correctly update them, if it is
called for arbitrary zoned device changes. Since there is not much need
for this ability, the easiest solution is to disallow any table reloads
that change the zoned settings, for devices that already have zone plug
resources. Specifically, if a device already has zone plug resources
allocated, it can only switch to another zoned table that also emulates
zone append. Also, it cannot change the device size or the zone size. A
device can switch to an error target.
Impact
CVE-2025-38140 has a CVSS score of 5.5 (Medium). The vector is requires local access, low privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. No fixed version is listed yet, so configuration controls and monitoring matter more in the interim.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Frequently Asked Questions
- What is CVE-2025-38140? CVE-2025-38140 is a medium-severity security vulnerability. No fixed version is listed yet.
- How severe is CVE-2025-38140? CVE-2025-38140 has a CVSS score of 5.5 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Is there a fix for CVE-2025-38140? No fixed version is listed for CVE-2025-38140 yet. Monitor the advisory for updates and apply mitigations in the interim.
- Is CVE-2025-38140 exploitable, and should I be worried? Whether CVE-2025-38140 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2025-38140 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.