CVE-2026-63902

Out-of-bounds read via short interrupt packet

Published Jul 19, 2026 · Updated Jul 19, 2026

An out-of-bounds read in the Linux Kernel cypress_m8 driver allows physically proximate attackers to read past a short USB packet. cypress_read_int_callback reads a one- or two-byte status header without verifying that the completed interrupt transfer contains it. Exploitation requires a connected Cypress-format USB serial device; the record demonstrates a one-byte invalid read but establishes neither data disclosure nor reliable service interruption.

CVSS severity3.5
Low
EPSS probability0.22%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

An out-of-bounds read in the Linux Kernel cypress_m8 driver allows physically proximate attackers to read past a short USB packet. cypress_read_int_callback reads a one- or two-byte status header without verifying that the completed interrupt transfer contains it. Exploitation requires a connected Cypress-format USB serial device; the record demonstrates a one-byte invalid read but establishes neither data disclosure nor reliable service interruption.

The record

CVE
CVE-2026-63902
Published
Jul 19, 2026
Updated
Jul 19, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
T1200
Attack vector
physical
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 19, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 19, 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=2.6.26
  2. Affected versionversion=3416eaa1f8f8d516b77de514e14cf8da256d28fb <44f9bab8df7750a1e2a4d6cc22d7c9c2dc096aed
  3. Affected versionversion=3416eaa1f8f8d516b77de514e14cf8da256d28fb <4a4cb0021ebe1fcadb52e04d19ed8d71470a530b
  4. Affected versionversion=3416eaa1f8f8d516b77de514e14cf8da256d28fb <90664556916de22467097d4c8ceb716d597a5c32
  5. Affected versionversion=3416eaa1f8f8d516b77de514e14cf8da256d28fb <9f9bfc80c67f35a275820da7e83a35dface08281
  6. Affected versionversion=3416eaa1f8f8d516b77de514e14cf8da256d28fb <aaa66708bfb1dca2acd219d1c1582f9f6d5492cb
  7. Affected versionversion=3416eaa1f8f8d516b77de514e14cf8da256d28fb <ae03453f2c809ca3cf73753269fa6184dea7160f
  8. Affected versionversion=3416eaa1f8f8d516b77de514e14cf8da256d28fb <be50533fe7068e86eb7adb81988e6d6a3f6dfe53
  9. Affected versionversion=3416eaa1f8f8d516b77de514e14cf8da256d28fb <fcef31a5a85ccf3c313449a866ec6ed7e4132425

What conditions does exploitation require?

Attack vectorphysical
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=2.6.26; version=3416eaa1f8f8d516b77de514e14cf8da256d28fb <44f9bab8df7750a1e2a4d6cc22d7c9c2dc096aed; version=3416eaa1f8f8d516b77de514e14cf8da256d28fb <4a4cb0021ebe1fcadb52e04d19ed8d71470a530b; version=3416eaa1f8f8d516b77de514e14cf8da256d28fb <90664556916de22467097d4c8ceb716d597a5c32; version=3416eaa1f8f8d516b77de514e14cf8da256d28fb <9f9bfc80c67f35a275820da7e83a35dface08281; version=3416eaa1f8f8d516b77de514e14cf8da256d28fb <aaa66708bfb1dca2acd219d1c1582f9f6d5492cb; version=3416eaa1f8f8d516b77de514e14cf8da256d28fb <ae03453f2c809ca3cf73753269fa6184dea7160f; version=3416eaa1f8f8d516b77de514e14cf8da256d28fb <be50533fe7068e86eb7adb81988e6d6a3f6dfe53; version=3416eaa1f8f8d516b77de514e14cf8da256d28fb <fcef31a5a85ccf3c313449a866ec6ed7e4132425

Published CVSS scores

3.5Amazon LinuxCVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

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

Weakness, pattern, technique

T1200Hardware Additions

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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