CVE-2026-5072

Device crash via unchecked PTP interval shift

Published May 22, 2026 · Updated May 22, 2026

Bitwise shift error in Zephyr RTOS 4.3 and earlier allows remote attackers to crash PTP-enabled devices with crafted PTP packets. The PTP port code stores an unvalidated negative log_announce_interval and later shifts a 64-bit timeout value by its negation. Exposure requires PTP processing on the adjacent network; outcomes are a trap-driven crash or a zero-timeout resource-starvation loop.

CVSS severity6.5
Medium
EPSS probability0.30%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Bitwise shift error in Zephyr RTOS 4.3 and earlier allows remote attackers to crash PTP-enabled devices with crafted PTP packets. The PTP port code stores an unvalidated negative log_announce_interval and later shifts a 64-bit timeout value by its negation. Exposure requires PTP processing on the adjacent network; outcomes are a trap-driven crash or a zero-timeout resource-starvation loop.

The record

CVE
CVE-2026-5072
Published
May 22, 2026
Updated
May 22, 2026
Vendor
Zephyr Project
Product
Zephyr RTOS
Classifications
CWE-1335, T1499.004
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 22, 2026CVE publishedPublication date reported by the CVE source.
  2. May 22, 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=* <=4.3

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

Zephyr Project · Zephyr RTOSversion=* <=4.3

Published CVSS scores

6.5Zephyr ProjectCVSS:3.1/AV:A/AC:L/PR:N/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-1335Incorrect Bitwise Shift of Integer
T1499.004Application 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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