CVE-2026-74340

Kernel memory disclosure via unchecked firmware register count

Published Aug 15, 2026 · Updated Aug 15, 2026

Out-of-bounds read in the Linux wcn36xx driver allows physically proximate attackers to disclose heap-buffer contents. The PRINT_REG_INFO handler trusts firmware-controlled rsp->count as the loop bound for rsp->regs[] without checking the received message length. Exposure requires the wcn36xx driver for Qualcomm WCN3660 or WCN3680 hardware and a malformed firmware indication; the read can disclose kernel heap data or crash the kernel.

CVSS severity8.1
High
EPSS probability0.27%
Next 30 days · Sep 17, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds read in the Linux wcn36xx driver allows physically proximate attackers to disclose heap-buffer contents. The PRINT_REG_INFO handler trusts firmware-controlled rsp->count as the loop bound for rsp->regs[] without checking the received message length. Exposure requires the wcn36xx driver for Qualcomm WCN3660 or WCN3680 hardware and a malformed firmware indication; the read can disclose kernel heap data or crash the kernel.

The record

CVE
CVE-2026-74340
Published
Aug 15, 2026
Updated
Aug 15, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-125, T1499
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 15, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 15, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=4.11
  2. Affected versionversion=43efa3c0f241e04862be8e6a68ff765d36cde1ba <0907c06dccae9e3c8d5a68eb9014beec73a36e79
  3. Affected versionversion=43efa3c0f241e04862be8e6a68ff765d36cde1ba <22b0b8572a64362531dd0ed499b75e16282aeb2b
  4. Affected versionversion=43efa3c0f241e04862be8e6a68ff765d36cde1ba <23d210877968657bd07e1a517e0b516db20a1d80
  5. Affected versionversion=43efa3c0f241e04862be8e6a68ff765d36cde1ba <3cf92b44c4fb88a5e8de8733a4494c0956606bca
  6. Affected versionversion=43efa3c0f241e04862be8e6a68ff765d36cde1ba <64228dfc4247aca178c01e5a37af7d8dcc7a6089
  7. Affected versionversion=43efa3c0f241e04862be8e6a68ff765d36cde1ba <df2187acfca6c6cca372c5d35f42394d9c270b09
  8. Affected versionversion=43efa3c0f241e04862be8e6a68ff765d36cde1ba <f03782f7f41f2afee5076a1ef08ced5649218771
  9. Affected versionversion=43efa3c0f241e04862be8e6a68ff765d36cde1ba <f987efff29a5fe45320ea5991c9d5cb98b676953

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=4.11; version=43efa3c0f241e04862be8e6a68ff765d36cde1ba <0907c06dccae9e3c8d5a68eb9014beec73a36e79; version=43efa3c0f241e04862be8e6a68ff765d36cde1ba <22b0b8572a64362531dd0ed499b75e16282aeb2b; version=43efa3c0f241e04862be8e6a68ff765d36cde1ba <23d210877968657bd07e1a517e0b516db20a1d80; version=43efa3c0f241e04862be8e6a68ff765d36cde1ba <3cf92b44c4fb88a5e8de8733a4494c0956606bca; version=43efa3c0f241e04862be8e6a68ff765d36cde1ba <64228dfc4247aca178c01e5a37af7d8dcc7a6089; version=43efa3c0f241e04862be8e6a68ff765d36cde1ba <df2187acfca6c6cca372c5d35f42394d9c270b09; version=43efa3c0f241e04862be8e6a68ff765d36cde1ba <f03782f7f41f2afee5076a1ef08ced5649218771; version=43efa3c0f241e04862be8e6a68ff765d36cde1ba <f987efff29a5fe45320ea5991c9d5cb98b676953

Published CVSS scores

6.8Amazon LinuxCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H
8.1LinuxCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
5.5Oracle LinuxCVSS: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 11, 2026Sep 17, 2026
Latest reporting daySep 17, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-125Out-of-bounds Read
T1499Endpoint Denial of Service

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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