CVE-2026-89102 (GCVE-0-2026-89102)

Vulnerability from cvelistv5 – Published: 2026-09-27 09:22 – Updated: 2026-09-29 16:04
VLAI
Title
OCSP stapling v2 multi accepts non-CA chain certificates as issuers
Summary
In wolfSSL versions 5.7.2 through 5.9.2 there is a client-side implementation flaw in RFC 6961, multiple OCSP response stapling, which can lead to certificate forgery. When a wolfSSL client enables OCSP stapling with the HAVE_CERTIFICATE_STATUS_REQUEST_V2 feature and calls wolfSSL_UseOCSPStaplingV2(ssl, WOLFSSL_CSR2_OCSP_MULTI, options), the client accepts any certificate in the peer's chain as a certificate authority without verifying that the certificate is actually authorized to act as one. This means that an attacker who possesses any certificate that chains to a CA trusted by the client (along with its private key) can forge certificates for arbitrary identities that will be accepted as valid by the client. The end entity certificate of the server is stored in the persistent trust store, affecting subsequent connections that reuse the context even when OCSP multi usage is not employed. Found by internal wolfSSL testing.
Severity
8.3 (High)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-29 16:03 UTC
CWE
  • CWE-295 - Improper Certificate Validation
Assigner
wolfSSL CNA under the icscert root
CNA scorecard B 80/100 over 51 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
wolfSSL wolfSSL Affected: 5.7.2 , ≤ 5.9.2 (semver)
guessed Create a notification for this product.
Date Public
2026-09-26 12:00
Show details on NVD website
To clipboard 

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