CVE-2026-43330

Kernel memory corruption via undersized HMAC key buffer

Published May 8, 2026 · Updated May 8, 2026

Out-of-bounds access in the CAAM crypto driver in Linux Kernel allows local users to corrupt kernel memory via a long HMAC key. In caamalg_qi2.c, the ahash_setkey path copies keylen bytes with kmemdup but submits the larger DMA-aligned length, reading beyond the temporary key buffer. Exploitation requires unprivileged local AF_ALG access and a registered CAAM QI2 driver; consequences include kernel-heap disclosure, corruption, or a crash.

CVSS severity7.8
High
EPSS probability0.13%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds access in the CAAM crypto driver in Linux Kernel allows local users to corrupt kernel memory via a long HMAC key. In caamalg_qi2.c, the ahash_setkey path copies keylen bytes with kmemdup but submits the larger DMA-aligned length, reading beyond the temporary key buffer. Exploitation requires unprivileged local AF_ALG access and a registered CAAM QI2 driver; consequences include kernel-heap disclosure, corruption, or a crash.

The record

CVE
CVE-2026-43330
Published
May 8, 2026
Updated
May 8, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-787, T1499.004
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 8, 2026CVE publishedPublication date reported by the CVE source.
  2. May 8, 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=199354d7fb6eaa2cc5bb650af0bca624baffee35 <31022cfde5235c45fa765f0aabeff5f0652852f2
  2. Affected versionversion=199354d7fb6eaa2cc5bb650af0bca624baffee35 <80688afb9c35b3934ce2d6be9973758915e2e0ef
  3. Affected versionversion=199354d7fb6eaa2cc5bb650af0bca624baffee35 <aa545df011338df13f0833fc1fabcb15c0521959
  4. Affected versionversion=199354d7fb6eaa2cc5bb650af0bca624baffee35 <c2fb4984fe09fc176fe4c12d5e3edf626df6511d
  5. Affected versionversion=199354d7fb6eaa2cc5bb650af0bca624baffee35 <cebc5ebd958346195b77f42d0cd5141b4e448fae
  6. Affected versionversion=6.3

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=199354d7fb6eaa2cc5bb650af0bca624baffee35 <31022cfde5235c45fa765f0aabeff5f0652852f2; version=199354d7fb6eaa2cc5bb650af0bca624baffee35 <80688afb9c35b3934ce2d6be9973758915e2e0ef; version=199354d7fb6eaa2cc5bb650af0bca624baffee35 <aa545df011338df13f0833fc1fabcb15c0521959; version=199354d7fb6eaa2cc5bb650af0bca624baffee35 <c2fb4984fe09fc176fe4c12d5e3edf626df6511d; version=199354d7fb6eaa2cc5bb650af0bca624baffee35 <cebc5ebd958346195b77f42d0cd5141b4e448fae; version=6.3

Published CVSS scores

7.1Oracle LinuxCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
7.8Linux Kernel CNACVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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.

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

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-787Out-of-bounds Write
T1499.004Application or System Exploitation

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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