CVE-2026-31790 (GCVE-0-2026-31790)
Vulnerability from cvelistv5
Published
2026-04-07 22:00
Modified
2026-05-12 12:09
Severity ?
CWE
  • CWE-754 - Improper Check for Unusual or Exceptional Conditions
Summary
Issue summary: Applications using RSASVE key encapsulation to establish a secret encryption key can send contents of an uninitialized memory buffer to a malicious peer. Impact summary: The uninitialized buffer might contain sensitive data from the previous execution of the application process which leads to sensitive data leakage to an attacker. RSA_public_encrypt() returns the number of bytes written on success and -1 on error. The affected code tests only whether the return value is non-zero. As a result, if RSA encryption fails, encapsulation can still return success to the caller, set the output lengths, and leave the caller to use the contents of the ciphertext buffer as if a valid KEM ciphertext had been produced. If applications use EVP_PKEY_encapsulate() with RSA/RSASVE on an attacker-supplied invalid RSA public key without first validating that key, then this may cause stale or uninitialized contents of the caller-provided ciphertext buffer to be disclosed to the attacker in place of the KEM ciphertext. As a workaround calling EVP_PKEY_public_check() or EVP_PKEY_public_check_quick() before EVP_PKEY_encapsulate() will mitigate the issue. The FIPS modules in 3.6, 3.5, 3.4, 3.3, 3.1 and 3.0 are affected by this issue.
References
Impacted products
Vendor Product Version
OpenSSL OpenSSL Version: 3.6.0   ≤
Version: 3.5.0   ≤
Version: 3.4.0   ≤
Version: 3.3.0   ≤
Version: 3.0.0   ≤
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