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CVE Record

CVE-2026-43330: crypto: caam - fix overflow on long hmac keys

In the Linux kernel, the following vulnerability has been resolved: crypto: caam - fix overflow on long hmac keys When a key longer than block size is supplied, it is copied and then hashed into the real key. The memory allocated for the copy needs to be rounded to DMA cache alignment, as otherwise the hashed key may corrupt neighbouring memory. The copying is performed using kmemdup, however this leads to an overflow: reading more bytes (aligned_len - keylen) from the keylen source buffer. Fix this by replacing kmemdup with kmalloc, followed by memcpy.

HighCVSS 7.8Not KEV-listedUpdated
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Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

CVE-2026-43330 is a Linux kernel flaw in the CAAM cryptographic driver. A local user or process could trigger memory corruption by using overly long HMAC keys. The reported impact is high because confidentiality, integrity, and availability may all be affected. No source provided indicates active exploitation.

Executive priority

Prioritize remediation in normal high-severity kernel patch cycles, faster for shared or security-sensitive systems. This is not currently evidenced as internet-exploited, but local kernel memory corruption can create serious business risk if abused after initial access.

Technical view

The CAAM crypto code mishandles HMAC keys longer than the block size. A kmemdup copy can read beyond the source buffer when DMA cache alignment padding is involved. The kernel fix replaces kmemdup with kmalloc plus memcpy to avoid the overflow condition.

Likely exposure

Exposure is most relevant to Linux systems running affected kernel versions with the CAAM crypto driver in use. The CVSS vector is local, low complexity, privileges required, and no user interaction. Exact distribution package impact requires vendor mapping.

Exploitation context

Sources rate this as CVSS 7.8 high with local authenticated access required. The bundle does not cite public exploitation, weaponized proof of concept, or CISA KEV listing. Treat as important for multi-user, appliance, and embedded Linux environments using this driver.

Researcher notes

The CVE record provides a clear root cause and stable kernel commit references, but no exploit status or detailed distro matrix. Validate exposure by driver presence and kernel lineage. Avoid assuming all Linux systems are affected without vendor-specific package confirmation.

Mitigation direction

  • Update to a Linux kernel version containing the referenced stable fixes.
  • Check your Linux distribution or device vendor advisory for packaged kernel updates.
  • Prioritize systems where the CAAM crypto driver is enabled or required.
  • If no update exists, ask the vendor for supported risk-reduction guidance.

Validation and detection

  • Inventory Linux kernel versions across affected fleets.
  • Check whether the CAAM crypto driver is present and enabled.
  • Map running kernels to vendor advisories and referenced stable commits.
  • Confirm patched kernels are installed and active after reboot.
Prepared
Confidence
medium
Sources
7

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

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CVE-2026-43330 mapping review

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Vulnerability profileCVE Program record
Severity
High
CVSS
7.8 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

1CVSS vectors
3Timeline events
0ADP providers
6Source links

CVSS vector scores

1 official score

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
7.8CVSS 3.1HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H1.85.9Linux

Vulnerability scoring details

Base CVSS 3.1 score

7.8High
CVSS 3.1 vector shape for CVE-2026-43330Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  2. CVE publishedCVE Program

    The CVE record was published.

  3. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
LinuxLinux199354d7fb6eaa2cc5bb650af0bca624baffee35, 199354d7fb6eaa2cc5bb650af0bca624baffee35, 199354d7fb6eaa2cc5bb650af0bca624baffee35, 199354d7fb6eaa2cc5bb650af0bca624baffee35, 199354d7fb6eaa2cc5bb650af0bca624baffee35unaffected
LinuxLinux6.3, 0, 6.6.134, 6.12.81, 6.18.22, 6.19.12, 7.0affected
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.