CVE Catalog

CVE-2026-31790

HighCVSS 7.5
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Elevated risk
1.20%

65th percentile - higher than 65% of all known CVEs

Summary

Vulnerability in OpenSSL related to RSASVE, where a failed RSA encryption may return success, leaving an uninitialized buffer. An attacker can exploit this to leak sensitive data from previous process operations.

Risk Assessment

Risk of leaking confidential data, such as keys or passwords, to an unauthorized party. This could lead to a breach of communication confidentiality.

Recommendation

Always call EVP_PKEY_public_check() or EVP_PKEY_public_check_quick() before using EVP_PKEY_encapsulate() with an RSA public key. Update OpenSSL to a patched version.

Other vulnerabilities in OpenSSL

See all
Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS