cvedb.io
CVE-2021-4044
HIGH · CVSS 7.5
EPSS exploitation probability: 0%
Published 2021-12-14T19:15:07.807 · Last modified 2026-06-17T04:18:56.683

Summary

Internally libssl in OpenSSL calls X509_verify_cert() on the client side to verify a certificate supplied by a server. That function may return a negative return value to indicate an internal error (for example out of memory). Such a negative return value is mishandled by OpenSSL and will cause an IO function (such as SSL_connect() or SSL_do_handshake()) to not indicate success and a subsequent call to SSL_get_error() to return the value SSL_ERROR_WANT_RETRY_VERIFY. This return value is only supposed to be returned by OpenSSL if the application has previously called SSL_CTX_set_cert_verify_callback(). Since most applications do not do this the SSL_ERROR_WANT_RETRY_VERIFY return value from SSL_get_error() will be totally unexpected and applications may not behave correctly as a result. The

Affected products

openssl — openssl

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.