CVE-2026-31790 (GCVE-0-2026-31790)

Vulnerability from cvelistv5 – Published: 2026-04-07 22:00 – Updated: 2026-04-08 14:32
VLAI?
Title
Incorrect Failure Handling in RSA KEM RSASVE Encapsulation
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.
Severity ?
No CVSS data available.
CWE
  • CWE-754 - Improper Check for Unusual or Exceptional Conditions
Assigner
References
Impacted products
Vendor Product Version
OpenSSL OpenSSL Affected: 3.6.0 , < 3.6.2 (semver)
Affected: 3.5.0 , < 3.5.6 (semver)
Affected: 3.4.0 , < 3.4.5 (semver)
Affected: 3.3.0 , < 3.3.7 (semver)
Affected: 3.0.0 , < 3.0.20 (semver)
Create a notification for this product.
Date Public ?
2026-04-07 14:00
Credits
Simo Sorce (Red Hat) Nikola Pajkovsky
Show details on NVD website
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Sightings

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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