CVE-2026-23206
MediumIn the Linux kernel, the following vulnerability has been resolved: dpaa2-switch: prevent ZERO_SIZE_PTR dereference when num_ifs is zero The driver allocates arrays for ports, FDBs, and filter blocks using kcalloc() with ethsw->sw_attr.num_ifs as the element count. When the device reports zero interfaces (either due to hardware configuration or firmware issues), kcalloc(0, ...) returns ZERO_SIZE_PTR (0x10) instead of NULL. Later in dpaa2_switch_probe(), the NAPI initialization unconditionally accesses ethsw->ports[0]->netdev, which attempts to dereference ZERO_SIZE_PTR (address 0x10), resulting in a kernel panic. Add a check to ensure num_ifs is greater than zero after retrieving device attributes. This prevents the zero-sized allocations and subsequent invalid pointer dereference.
CVSS 3.1 score
5.5
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness type
CWE-476CVE-2026-23206 is a NULL Pointer Dereference vulnerability
What is NULL Pointer Dereference?
The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. Learn more on MITRE CWE
Affected versions
Linux kernel versions
5.13
and later are affected. Fixed in
5.15.200,
6.1.163,
6.6.124,
6.12.70,
6.18.10,
6.19
and their respective stable series.
References
The following references provide additional information about CVE-2026-23206 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.
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PatchKernel patch commithttps://git.kernel.org/stable/c/155eb99aff2920153bf21217ae29565fff81e6af
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PatchKernel patch commithttps://git.kernel.org/stable/c/2fcccca88456b592bd668db13aa1d29ed257ca2b
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PatchKernel patch commithttps://git.kernel.org/stable/c/4acc40db06ffd0fd92683505342b00c8a7394c60
Frequently asked questions
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What is CVE-2026-23206?
CVE-2026-23206 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 , classified as a NULL Pointer Dereference flaw (CWE-476) . It affects Linux kernel versions from 5.13 onward and has been patched in 5.15.200, 6.1.163, 6.6.124 and others. CVE-2026-23206 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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What is the CVSS score for CVE-2026-23206?
CVE-2026-23206 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H. -
Is there a patch available for CVE-2026-23206?
Yes — CVE-2026-23206 has been patched. Fixed versions include 5.15.200, 6.1.163, 6.6.124 and others. If you are running Linux kernel 5.13 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-23206 actively exploited?
No — CVE-2026-23206 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
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What is NULL Pointer Dereference (CWE-476)?
The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. View CWE-476 on MITRE CWE →