How severe is CVE-2026-55967?

CVE-2026-55967 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2026-55967 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (2nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-55967?

CVE-2026-55967 affects Wolfssl. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-55967?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2026-55967 have an EU (EUVD) identifier?

Yes. CVE-2026-55967 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-39493.

When was CVE-2026-55967 published?

CVE-2026-55967 was published on 2026-06-25 and last updated on 2026-06-26.

CVE-2026-55967

CVE-2026-55967 is a high-severity vulnerability in Wolfssl with a CVSS 3.x base score of 7.5. 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-323.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v4: 2.0
EPSS exploit prediction: 0% (2nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-39493
Weakness: CWE-323
Affected product: Wolfssl
Published: 2026-06-25
Last modified: 2026-06-26

Description

AES-GCM encryption/decryption with extremely large cumulative single message sizes (>64 GiB) were not properly rejected by the streaming APIs, allowing counter wrap, keystream reuse, and consequent plaintext recovery.

Frequently asked questions

What is CVE-2026-55967?: AES-GCM encryption/decryption with extremely large cumulative single message sizes (>64 GiB) were not properly rejected by the streaming APIs, allowing counter wrap, keystream reuse, and consequent plaintext recovery.
How severe is CVE-2026-55967?: CVE-2026-55967 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2026-55967 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (2nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-55967?: CVE-2026-55967 affects Wolfssl. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-55967?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-55967 have an EU (EUVD) identifier?: Yes. CVE-2026-55967 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-39493.
When was CVE-2026-55967 published?: CVE-2026-55967 was published on 2026-06-25 and last updated on 2026-06-26.

References

Affected products (1)

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

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