How severe is CVE-2026-5447?

CVE-2026-5447 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 none, integrity high, and availability none.

Is CVE-2026-5447 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (13th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-5447?

CVE-2026-5447 affects Wolfssl. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-5447?

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-2026-5447 have an EU (EUVD) identifier?

Yes. CVE-2026-5447 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-21183.

When was CVE-2026-5447 published?

CVE-2026-5447 was published on 2026-04-09 and last updated on 2026-06-17.

CVE-2026-5447

CVE-2026-5447 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-122.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v4: 6.3
EPSS exploit prediction: 0% (13th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-21183
Weakness: CWE-122
Affected product: Wolfssl
Published: 2026-04-09
Last modified: 2026-06-17

Description

Heap buffer overflow in CertFromX509 via AuthorityKeyIdentifier size confusion. A heap buffer overflow occurs when converting an X.509 certificate internally due to incorrect size handling of the AuthorityKeyIdentifier extension.

Frequently asked questions

What is CVE-2026-5447?: Heap buffer overflow in CertFromX509 via AuthorityKeyIdentifier size confusion. A heap buffer overflow occurs when converting an X.509 certificate internally due to incorrect size handling of the AuthorityKeyIdentifier extension.
How severe is CVE-2026-5447?: CVE-2026-5447 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 none, integrity high, and availability none.
Is CVE-2026-5447 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (13th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-5447?: CVE-2026-5447 affects Wolfssl. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-5447?: 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-2026-5447 have an EU (EUVD) identifier?: Yes. CVE-2026-5447 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-21183.
When was CVE-2026-5447 published?: CVE-2026-5447 was published on 2026-04-09 and last updated on 2026-06-17.

References

https://github.com/wolfSSL/wolfssl/pull/10112

Affected products (1)

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

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