Error code
Firefox MOZILLA_PKIX_ERROR_SELF_SIGNED_CERT
FIREFOXMOZILLA_PKIX_ERROR_SELF_SIGNED_CERT
Browser Error Code· An error code shown in a web browser when a page fails to load.
What it means
The certificate is self-signed and not issued by a trusted certificate authority.
How to fix it
- Accept the certificate only if you manage the server and trust it explicitly.
- For production sites replace with a certificate from a trusted CA such as Let's Encrypt.
- In Firefox you can permanently add an exception via Advanced > Accept the Risk.
Not affiliated with Firefox. Answer summarized from the manufacturer's manual linked above; consult that source for the authoritative procedure.
More Firefox codes
- MOZILLA_PKIX_ERROR_MITM_DETECTEDFirefox detected a likely man-in-the-middle attack on this connection
- SEC_ERROR_BAD_DERThe certificate contains invalid DER-encoded data and cannot be parsed
- SEC_ERROR_CERT_SIGNATURE_ALGORITHM_DISABLEDThe certificate uses a signature algorithm that Firefox has disabled for security reasons
- SEC_ERROR_EXPIRED_CERTIFICATEThe server's certificate has expired and the connection cannot be secured
- SEC_ERROR_INADEQUATE_KEY_USAGEThe certificate is being used for a purpose not permitted by its key usage extension
- SEC_ERROR_OCSP_FUTURE_RESPONSEThe OCSP certificate status response is dated in the future
- SEC_ERROR_OCSP_INVALID_SIGNING_CERTThe certificate that signed the OCSP response is not trusted
- SEC_ERROR_REUSED_ISSUER_AND_SERIALA different certificate with the same issuer and serial number was already seen
- SEC_ERROR_REVOKED_CERTIFICATEThe certificate has been revoked by the authority that issued it
- SEC_ERROR_UNKNOWN_ISSUERFirefox does not recognize the authority that signed the certificate
- SSL_ERROR_BAD_CERT_DOMAINThe certificate is valid but was issued for a different hostname
- SSL_ERROR_NO_CYPHER_OVERLAPFirefox and the server could not agree on any shared encryption algorithms