How severe is CVE-2026-6330?

CVE-2026-6330 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2026-6330 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-6330?

CVE-2026-6330 affects Wolfssl. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-6330?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-6330 have an EU (EUVD) identifier?

Yes. CVE-2026-6330 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-39570.

When was CVE-2026-6330 published?

CVE-2026-6330 was published on 2026-06-25 and last updated on 2026-06-27.

CVE-2026-6330

CVE-2026-6330 is a medium-severity vulnerability in Wolfssl with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-327.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v4: 6.3
EPSS exploit prediction: 0% (3rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-39570
Weakness: CWE-327
Affected product: Wolfssl
Published: 2026-06-25
Last modified: 2026-06-27

Description

The ML-KEM ARM64 NEON ciphertext comparison only compares half of the input, breaking the Fujisaki-Okamoto transform's implicit rejection and weakening IND-CCA2 security on that code path. The constant-time comparison effectively ignored part of the re-encrypted ciphertext, so a decapsulating party could fail to detect a manipulated ciphertext and proceed without the standard's required implicit rejection.

Frequently asked questions

What is CVE-2026-6330?: The ML-KEM ARM64 NEON ciphertext comparison only compares half of the input, breaking the Fujisaki-Okamoto transform's implicit rejection and weakening IND-CCA2 security on that code path. The constant-time comparison effectively ignored part of the re-encrypted ciphertext, so a decapsulating party could fail to detect a manipulated ciphertext and proceed without the standard's required implicit rejection.
How severe is CVE-2026-6330?: CVE-2026-6330 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2026-6330 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-6330?: CVE-2026-6330 affects Wolfssl. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-6330?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-6330 have an EU (EUVD) identifier?: Yes. CVE-2026-6330 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-39570.
When was CVE-2026-6330 published?: CVE-2026-6330 was published on 2026-06-25 and last updated on 2026-06-27.

References

Affected products (1)

cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*

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