CVE-2026-31660
MediumIn the Linux kernel, the following vulnerability has been resolved: nfc: pn533: allocate rx skb before consuming bytes pn532_receive_buf() reports the number of accepted bytes to the serdev core. The current code consumes bytes into recv_skb and may already hand a complete frame to pn533_recv_frame() before allocating a fresh receive buffer. If that alloc_skb() fails, the callback returns 0 even though it has already consumed bytes, and it leaves recv_skb as NULL for the next receive callback. That breaks the receive_buf() accounting contract and can also lead to a NULL dereference on the next skb_put_u8(). Allocate the receive skb lazily before consuming the next byte instead. If allocation fails, return the number of bytes already accepted.
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
Affected versions
Linux kernel versions
5.5
and later are affected. Fixed in
5.10.253,
5.15.203,
6.1.169,
6.6.135,
6.12.82,
6.18.23,
6.19.13,
7.0
and their respective stable series.
References
The following references provide additional information about CVE-2026-31660 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/07cb6c72e66ba548679f22ac29ad588da8999279
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PatchKernel patch commithttps://git.kernel.org/stable/c/16649adc2e19509104245ea1f349b629d858f11f
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PatchKernel patch commithttps://git.kernel.org/stable/c/21ae2cda66a55c759607bbf1d23cbaa42019d2de
Frequently asked questions
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What is CVE-2026-31660?
CVE-2026-31660 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 . It affects Linux kernel versions from 5.5 onward and has been patched in 5.10.253, 5.15.203, 6.1.169 and others. CVE-2026-31660 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-2026-31660?
CVE-2026-31660 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-2026-31660?
Yes — CVE-2026-31660 has been patched. Fixed versions include 5.10.253, 5.15.203, 6.1.169 and others. If you are running Linux kernel 5.5 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-31660 actively exploited?
No — CVE-2026-31660 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.