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.
{
"license": "CC-BY-4.0",
"sources": [
{
"html_url": "https://nvd.nist.gov/vuln/detail/CVE-2026-31790",
"url": "https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-31790",
"published": "2026-04-07T22:16:21.770Z",
"id": "CVE-2026-31790",
"imported": "2026-07-17T21:33:24.669Z",
"modified": "2026-06-17T10:34:28.237Z",
"database_specific": {
"status": "Modified"
}
},
{
"modified": "2026-05-12T15:31:16Z",
"url": "https://api.github.com/advisories/GHSA-vgxx-5xj5-q97x",
"published": "2026-04-08T00:30:26Z",
"id": "GHSA-vgxx-5xj5-q97x",
"imported": "2026-07-17T21:33:24.816Z",
"html_url": "https://github.com/advisories/GHSA-vgxx-5xj5-q97x"
},
{
"html_url": "https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-19969",
"url": "https://euvdservices.enisa.europa.eu/api/enisaid?id=EUVD-2026-19969",
"published": "2026-04-07T22:00:56Z",
"id": "EUVD-2026-19969",
"imported": "2026-07-17T21:33:34.787Z",
"modified": "2026-05-12T12:09:06Z"
}
]
}