CVE-2026-64355: Linux Kernel out-of-bounds read (CVSS 9.8)

Description

In the Linux kernel, the following vulnerability has been resolved: bpf: Reject fragmented frames in devmap Devmap broadcast redirects clone the packet for all but the last destination. For native XDP, that clone path copies only the linear xdp_frame data, while fragmented frames keep skb_shared_info in tailroom outside the linear area. Cloning such a frame leaves XDP_FLAGS_HAS_FRAGS set but without valid frag metadata, and the later free path can interpret uninitialized tail data as skb_shared_info, leading to an out-of-bounds access during frame return. Reject fragmented native XDP frames in dev_map_enqueue_clone(). Add the same restriction to the generic XDP clone path in dev_map_redirect_clone(). Generic XDP represents fragmented packets as nonlinear skbs, and rejecting them here keeps clone-based broadcast support aligned between native and generic XDP.

CVSS 3.1 breakdown

Attack vectorNetwork

Attack complexityLow

Privileges requiredNone

User interactionNone

ScopeUnchanged

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

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

Affected products

Linux Kernel≥ 5.14 < 5.15.212 · ≥ 5.16 < 6.1.178 · ≥ 6.13 < 6.18.39 · ≥ 6.19 < 7.1.4

Remediation

Fixed in

Linux Kernel≥ 5.15.212

Patch & vendor advisories

References

Related CVEs

Recent high-severity vulnerabilities sharing a weakness type.

Frequently asked

Is CVE-2026-64355 being actively exploited?

CVE-2026-64355 is not in the CISA KEV catalog. Its EPSS exploit probability is 0.51%.

How severe is CVE-2026-64355?

CVE-2026-64355 has a CVSS 3.1 base score of 9.8, rated critical. EPSS estimates a 0.51% probability of exploitation.

Which products are affected by CVE-2026-64355?

Affected products include Linux Kernel.

How do I fix CVE-2026-64355?

Upgrade affected software to a fixed version, for example Linux Kernel 5.15.212 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2026-64355 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

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