What is CVE-2026-98253?

CVE-2026-98253 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10, affecting Linux kernel versions from 5.10.20 onward and patched in 5.10.271, 5.15.222, 6.1.189 and others. CVE-2026-98253 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-98253?

CVE-2026-98253 has a CVSS score of 7.8 out of 10, rated High severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Is there a patch available for CVE-2026-98253?

Yes, CVE-2026-98253 has been patched. Fixed versions include 5.10.271, 5.15.222, 6.1.189 and others. If you are running Linux kernel 5.10.20 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-98253 actively exploited?

CVE-2026-98253 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-98253

High

In the Linux kernel, the following vulnerability has been resolved: RDMA/ucma: Serialize join and leave on copy_to_user failure rdma_join_multicast() queues RoCE work that later reads the ucma_multicast through event->param.ud.private_data, then list_add()s the CMA multicast at the head of id_priv->mc_list. rdma_leave_multicast() matches only by sockaddr and destroys the first hit. ucma_process_join() used to drop ctx->mutex after a successful join and retake it only if copy_to_user() failed. Two concurrent JOIN_MCAST calls with the same address can therefore insert a second CMA entry before the first thread's leave. leave then cancels the newer work and the older worker still dereferences the ucma_multicast that the first thread frees. Keep ctx->mutex held from rdma_join_multicast() through copy_to_user() and, on -EFAULT, through rdma_leave_multicast() so leave cannot miss this join. Do not leave if join itself failed: that path never published this address on mc_list, and a leave-by-addr would destroy an earlier successful join.

Package Linux Kernel

Published 2026-10-06

Last modified 2026-10-07

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

7.8

out of 10

High

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Vector string

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

Affected versions

Linux kernel versions 5.10.20, 5.11.3, 5.12 and later are affected. Fixed in 5.10.271, 5.15.222, 6.1.189, 6.6.158, 6.12.112, 6.18.54, 7.2.8, 7.3-rc4 and their respective stable series.

Affected from

≥ 5.10.20 ≥ 5.11.3 ≥ 5.12

Fixed in

✓ 5.10.271 5.10.x ✓ 5.15.222 5.15.x ✓ 6.1.189 6.1.x ✓ 6.6.158 6.6.x ✓ 6.12.112 6.12.x ✓ 6.18.54 6.18.x ✓ 7.2.8 7.2.x ✓ 7.3-rc4

References

8 total

Showing 5 of 8 references View all on NVD

Details

CVE ID CVE-2026-98253

Severity High

CVSS score 7.8 / 10

CVSS version 3.1

Published 2026-10-06

Modified 2026-10-07

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-98253?

CVE-2026-98253 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10 . It affects Linux kernel versions from 5.10.20 onward and has been patched in 5.10.271, 5.15.222, 6.1.189 and others. CVE-2026-98253 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-98253?

CVE-2026-98253 has a CVSS score of 7.8 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Is there a patch available for CVE-2026-98253?

Yes. CVE-2026-98253 has been patched. Fixed versions include 5.10.271, 5.15.222, 6.1.189 and others. If you are running Linux kernel 5.10.20 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-98253 actively exploited?

No. CVE-2026-98253 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.