CVE-2026-53188High· 8.8▾ Twilight

RDMA/core: Validate the passed in fops for ib_get_ucaps()

In the Linux kernel, the following vulnerability has been resolved: RDMA/core: Validate the passed in fops for ib_get_ucaps() Sashiko pointed out it is not safe to rely only on the devt because char/block alias so if the user finds a b…

▾ Twilight zone — High severity, or a signal on a lesser flaw

Depth score48/ 100 · Moderate

impact 48.4 · likelihood 0 · exploitation 0

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Proof of concept

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Published

Jun 25, 2026

Updated

Oct 19, 2026

CVSS

8.8

Vendor

Linux

Product

Linux

CWE

—

Depth score

48 · Moderate

EPSS

0.15% · p5

Platforms

—

Source

CVEORG

Vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

CISA SSVC

decided 2026-10-16

Exploitation: none
Automatable: no
Technical impact: total

Stakeholder-Specific Vulnerability Categorization from CISA's ADP record at CVE.org: whether exploitation is observed, whether an attack can be automated, and how much of the system is at stake. The CVSS score shown above comes from the assigning CNA record, not NVD.

EPSS history

Exploit-prediction probability, daily snapshots since Oct 16.

0.1% → 0.2%

Timeline

Disclosure to exploitation, from the record and what we observed since indexing it.

4 events · 123 days

Jun 25, 2026Published
Disclosed via CVEORG
Oct 16, 2026EPSS first tracked
0.1%
Oct 19, 2026Record revised
Last analysed / modified upstream
Oct 26, 2026EPSS peak
0.1% → 0.2%

Linux #cve.org

Affected

Linux >= 61e51682816d395307f78ae06d640089054c28ab < 96b6e98ff12d50ed5817230c6f1188e1150d225d
Linux >= 61e51682816d395307f78ae06d640089054c28ab < aa181287ebdcc53ee0ba5c2f8243e2d541ebc19b
Linux >= 61e51682816d395307f78ae06d640089054c28ab < 4a1b1ac2744694a2ecd66a84bdb1445f4ef24bee
Linux 6.15

Full technical detail▾

Overview

In the Linux kernel, the following vulnerability has been resolved:

RDMA/core: Validate the passed in fops for ib_get_ucaps()

Sashiko pointed out it is not safe to rely only on the devt because char/block alias so if the user finds a block device with the same dev_t it can masquerade as a ucap cdev fd.

Test the f_ops to only accept authentic cdevs.

Affected

Linux >= 61e51682816d395307f78ae06d640089054c28ab < 96b6e98ff12d50ed5817230c6f1188e1150d225d
Linux >= 61e51682816d395307f78ae06d640089054c28ab < aa181287ebdcc53ee0ba5c2f8243e2d541ebc19b
Linux >= 61e51682816d395307f78ae06d640089054c28ab < 4a1b1ac2744694a2ecd66a84bdb1445f4ef24bee
Linux 6.15

Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

References

Related vulnerabilities

Connected by shared product, vendor, weakness, or advisory.

#cve.org

RDMA/core: Validate the passed in fops for ib_get_ucaps()

▾ Twilight zone — High severity, or a signal on a lesser flaw

Depth score48/ 100 · Moderate

impact 48.4 · likelihood 0 · exploitation 0

Overview

In the Linux kernel, the following vulnerability has been resolved:

RDMA/core: Validate the passed in fops for ib_get_ucaps()

Sashiko pointed out it is not safe to rely only on the devt because char/block alias so if the user finds a block device with the same dev_t it can masquerade as a ucap cdev fd.

Test the f_ops to only accept authentic cdevs.