CVE-2022-3358
Published: 11 October 2022
Summary
CVE-2022-3358 is a high-severity NULL Pointer Dereference (CWE-476) vulnerability in Openssl Openssl. Its CVSS base score is 7.5 (High).
Operationally, ranked in the top 4.5% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
Deeper analysis
OpenSSL versions 3.0.0 through 3.0.5 contain a flaw in the handling of legacy custom ciphers created via the deprecated EVP_CIPHER_meth_new() function and related calls. When an application passes NID_undef as the NID and subsequently invokes encryption or decryption initialization routines such as EVP_EncryptInit_ex2(), EVP_DecryptInit_ex2(), or EVP_CipherInit_ex2(), the library incorrectly matches and loads the NULL cipher from the default provider instead of using the intended custom implementation. This causes plaintext to be emitted directly as ciphertext. Only applications that explicitly register and use such a custom cipher with NID_undef are affected; standard SSL/TLS usage is not impacted.
An unauthenticated remote attacker can exploit the issue over the network to obtain plaintext data that should have been encrypted, resulting in a high confidentiality impact without requiring user interaction. The flaw is triggered solely by the affected application’s own use of the legacy API; no special network position beyond the ability to observe the resulting traffic is needed.
The official OpenSSL advisory and subsequent vendor notices, including those from NetApp and Gentoo, state that the defect is resolved in version 3.0.6. Upgrading to a fixed release or ensuring that custom ciphers are registered with a valid NID are the recommended mitigations. The EPSS score has remained flat at its peak value since disclosure, indicating no material increase in observed exploitation interest.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2022-7013
Vulnerability details
OpenSSL supports creating a custom cipher via the legacy EVP_CIPHER_meth_new() function and associated function calls. This function was deprecated in OpenSSL 3.0 and application authors are instead encouraged to use the new provider mechanism in order to implement custom ciphers.…
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OpenSSL versions 3.0.0 to 3.0.5 incorrectly handle legacy custom ciphers passed to the EVP_EncryptInit_ex2(), EVP_DecryptInit_ex2() and EVP_CipherInit_ex2() functions (as well as other similarly named encryption and decryption initialisation functions). Instead of using the custom cipher directly it incorrectly tries to fetch an equivalent cipher from the available providers. An equivalent cipher is found based on the NID passed to EVP_CIPHER_meth_new(). This NID is supposed to represent the unique NID for a given cipher. However it is possible for an application to incorrectly pass NID_undef as this value in the call to EVP_CIPHER_meth_new(). When NID_undef is used in this way the OpenSSL encryption/decryption initialisation function will match the NULL cipher as being equivalent and will fetch this from the available providers. This will succeed if the default provider has been loaded (or if a third party provider has been loaded that offers this cipher). Using the NULL cipher means that the plaintext is emitted as the ciphertext. Applications are only affected by this issue if they call EVP_CIPHER_meth_new() using NID_undef and subsequently use it in a call to an encryption/decryption initialisation function. Applications that only use SSL/TLS are not impacted by this issue. Fixed in OpenSSL 3.0.6 (Affected 3.0.0-3.0.5).
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
No mitigating controls mapped yet. The per-CVE control annotator has not reached this CVE.