CVE-2026-31660

Local service crash via PN533 receive-buffer NULL dereference

Published Apr 24, 2026 · Updated Apr 24, 2026

NULL-pointer dereference in the Linux Kernel PN533 UART driver allows local users to crash the system through NFC serial input. In pn532_receive_buf(), a completed frame can clear recv_skb before alloc_skb() fails; the callback then reports zero consumed bytes, and the next byte reaches skb_put_u8() with a NULL buffer. Reachability requires the PN533 UART receive path and an allocation failure after a complete frame; the bounded consequence is an availability-only kernel crash.

CVSS severity5.5
Medium
EPSS probability0.11%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

NULL-pointer dereference in the Linux Kernel PN533 UART driver allows local users to crash the system through NFC serial input. In pn532_receive_buf(), a completed frame can clear recv_skb before alloc_skb() fails; the callback then reports zero consumed bytes, and the next byte reaches skb_put_u8() with a NULL buffer. Reachability requires the PN533 UART receive path and an allocation failure after a complete frame; the bounded consequence is an availability-only kernel crash.

The record

CVE
CVE-2026-31660
Published
Apr 24, 2026
Updated
Apr 24, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 24, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 24, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=5.5
  2. Affected versionversion=c656aa4c27b17a8c70da223ed5ab42145800d6b5 <07cb6c72e66ba548679f22ac29ad588da8999279
  3. Affected versionversion=c656aa4c27b17a8c70da223ed5ab42145800d6b5 <16649adc2e19509104245ea1f349b629d858f11f
  4. Affected versionversion=c656aa4c27b17a8c70da223ed5ab42145800d6b5 <21ae2cda66a55c759607bbf1d23cbaa42019d2de
  5. Affected versionversion=c656aa4c27b17a8c70da223ed5ab42145800d6b5 <2ca64fb7e2d2ae14619dd204d4f2f0a601f421fb
  6. Affected versionversion=c656aa4c27b17a8c70da223ed5ab42145800d6b5 <7e37da42eda45d7859d9273fc7e225d8df458038
  7. Affected versionversion=c656aa4c27b17a8c70da223ed5ab42145800d6b5 <8b71299d587d9e4c830c18afb884c80ddb30ad28
  8. Affected versionversion=c656aa4c27b17a8c70da223ed5ab42145800d6b5 <a9495069b43b8634c1ae0042e888766c34f66637
  9. Affected versionversion=c656aa4c27b17a8c70da223ed5ab42145800d6b5 <c71ba669b570c7b3f86ec875be222ea11dacb352

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=5.5; version=c656aa4c27b17a8c70da223ed5ab42145800d6b5 <07cb6c72e66ba548679f22ac29ad588da8999279; version=c656aa4c27b17a8c70da223ed5ab42145800d6b5 <16649adc2e19509104245ea1f349b629d858f11f; version=c656aa4c27b17a8c70da223ed5ab42145800d6b5 <21ae2cda66a55c759607bbf1d23cbaa42019d2de; version=c656aa4c27b17a8c70da223ed5ab42145800d6b5 <2ca64fb7e2d2ae14619dd204d4f2f0a601f421fb; version=c656aa4c27b17a8c70da223ed5ab42145800d6b5 <7e37da42eda45d7859d9273fc7e225d8df458038; version=c656aa4c27b17a8c70da223ed5ab42145800d6b5 <8b71299d587d9e4c830c18afb884c80ddb30ad28; version=c656aa4c27b17a8c70da223ed5ab42145800d6b5 <a9495069b43b8634c1ae0042e888766c34f66637; version=c656aa4c27b17a8c70da223ed5ab42145800d6b5 <c71ba669b570c7b3f86ec875be222ea11dacb352

Published CVSS scores

5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Endpoint Denial of Service: Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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