How severe is CVE-2026-6678?

CVE-2026-6678 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2026-6678 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (9th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-6678?

CVE-2026-6678 affects Wolfssl. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-6678?

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

Does CVE-2026-6678 have an EU (EUVD) identifier?

Yes. CVE-2026-6678 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-39558.

When was CVE-2026-6678 published?

CVE-2026-6678 was published on 2026-06-25 and last updated on 2026-07-01.

CVE-2026-6678

CVE-2026-6678 is a medium-severity vulnerability in Wolfssl with a CVSS 3.x base score of 5.3. 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-191.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v4: 1.0
EPSS exploit prediction: 0% (9th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-39558
Weakness: CWE-191
Affected product: Wolfssl
Published: 2026-06-25
Last modified: 2026-07-01

Description

Integer underflow in wc_PKCS7_DecryptOri when handling crafted Other Recipient Info, leading to incorrect length handling during decryption.

Frequently asked questions

What is CVE-2026-6678?: Integer underflow in wc_PKCS7_DecryptOri when handling crafted Other Recipient Info, leading to incorrect length handling during decryption.
How severe is CVE-2026-6678?: CVE-2026-6678 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2026-6678 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (9th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-6678?: CVE-2026-6678 affects Wolfssl. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-6678?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-6678 have an EU (EUVD) identifier?: Yes. CVE-2026-6678 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-39558.
When was CVE-2026-6678 published?: CVE-2026-6678 was published on 2026-06-25 and last updated on 2026-07-01.

References

Affected products (1)

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

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