How severe is CVE-2026-11310?

CVE-2026-11310 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-2026-11310 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (4th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-11310?

CVE-2026-11310 affects Wolfssl. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-11310?

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-2026-11310 have an EU (EUVD) identifier?

Yes. CVE-2026-11310 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-39548.

When was CVE-2026-11310 published?

CVE-2026-11310 was published on 2026-06-25 and last updated on 2026-06-26.

CVE-2026-11310

CVE-2026-11310 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-295.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v4: 8.7
EPSS exploit prediction: 0% (4th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-39548
Weakness: CWE-295
Affected product: Wolfssl
Published: 2026-06-25
Last modified: 2026-06-26

Description

X.509 trust-chain bypass in the OpenSSL compatibility certificate verifier (wolfSSL_X509_verify_cert()). This affects only builds with --enable-opensslextra (OPENSSL_EXTRA) and whose application validates certificates by calling X509_verify_cert() with caller-supplied untrusted intermediate certificates; for those users it is critical, otherwise the library is unaffected. In particular, native wolfSSL TLS/DTLS usage is not impacted. wolfSSL's X509_verify_cert() temporarily loads each caller-supplied untrusted intermediate into the certificate manager but failed to drop them before the trusted-store check, so an untrusted intermediate could anchor the path itself. An attacker can present a chain that never reaches a configured trust anchor and have it accepted, resulting in acceptance of an attacker-controlled certificate. This is certificate verification independent of TLS (e.g. S/MIME/CMS, code/firmware signing, JWT/JWS x5c), is not specific to any key type or algorithm, and a single untrusted intermediate suffices. The default wolfSSL TLS handshake (WOLFSSL_VERIFY_PEER) is not affected; only TLS applications doing manual or deferred peer verification through this API are, which also requires --enable-sessioncerts.

Frequently asked questions

What is CVE-2026-11310?: X.509 trust-chain bypass in the OpenSSL compatibility certificate verifier (wolfSSL_X509_verify_cert()). This affects only builds with --enable-opensslextra (OPENSSL_EXTRA) and whose application validates certificates by calling X509_verify_cert() with caller-supplied untrusted intermediate certificates; for those users it is critical, otherwise the library is unaffected. In particular, native wolfSSL TLS/DTLS usage is not impacted. wolfSSL's X509_verify_cert() temporarily loads each caller-supplied untrusted intermediate into the certificate manager but failed to drop them before the trusted-store check, so an untrusted intermediate could anchor the path itself. An attacker can present a chain that never reaches a configured trust anchor and have it accepted, resulting in acceptance of an attacker-controlled certificate. This is certificate verification independent of TLS (e.g. S/MIME/CMS, code/firmware signing, JWT/JWS x5c), is not specific to any key type or algorithm, and a single untrusted intermediate suffices. The default wolfSSL TLS handshake (WOLFSSL_VERIFY_PEER) is not affected; only TLS applications doing manual or deferred peer verification through this API are, which also requires --enable-sessioncerts.
How severe is CVE-2026-11310?: CVE-2026-11310 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-2026-11310 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (4th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-11310?: CVE-2026-11310 affects Wolfssl. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-11310?: 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-2026-11310 have an EU (EUVD) identifier?: Yes. CVE-2026-11310 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-39548.
When was CVE-2026-11310 published?: CVE-2026-11310 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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