CVE-2026-31790

HIGH EPSS 57.8%
Published Apr 7, 20262mo ago · Modified Jun 17, 20261w ago
7.5 CVSS 3.1
High
Find Similar
Published Apr 7, 2026 2mo ago
Last Modified Jun 17, 2026 1w ago

Description

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.

CVSS Details

Base Score
7.5
Exploitability
3.9
Impact
3.6
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality High
Integrity None
Availability None

Threat Intelligence

EPSS Exploit Probability
57.8% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-754

Affected Products 5

VendorProductVersionRange
opensslopenssl*≥3.0.0  –  <3.0.20
opensslopenssl*≥3.3.0  –  <3.3.7
opensslopenssl*≥3.4.0  –  <3.4.5
opensslopenssl*≥3.5.0  –  <3.5.6
opensslopenssl*≥3.6.0  –  <3.6.2

References 7

  • cert-portal.siemens.com https://cert-portal.siemens.com/productcert/html/ssa-032379.html
  • github.com https://github.com/openssl/openssl/commit/001e01db3e996e13ffc72386fe79d03a6683b5ac
    Patch
  • github.com https://github.com/openssl/openssl/commit/abd8b2eec7e3f3fda60ecfb68498b246b52af482
    Patch
  • github.com https://github.com/openssl/openssl/commit/b922e24e5b23ffb9cb9e14cadff23d91e9f7e406
    Patch
  • github.com https://github.com/openssl/openssl/commit/d5f8e71cd0a54e961d0c3b174348f8308486f790
    Patch
  • github.com https://github.com/openssl/openssl/commit/eed200f58cd8645ed77e46b7e9f764e284df379e
    Patch
  • openssl-library.org https://openssl-library.org/news/secadv/20260407.txt
    Vendor Advisory

Remediation

  • github.com https://github.com/openssl/openssl/commit/001e01db3e996e13ffc72386fe79d03a6683b5ac
    Patch
  • github.com https://github.com/openssl/openssl/commit/abd8b2eec7e3f3fda60ecfb68498b246b52af482
    Patch
  • github.com https://github.com/openssl/openssl/commit/b922e24e5b23ffb9cb9e14cadff23d91e9f7e406
    Patch
  • github.com https://github.com/openssl/openssl/commit/d5f8e71cd0a54e961d0c3b174348f8308486f790
    Patch
  • github.com https://github.com/openssl/openssl/commit/eed200f58cd8645ed77e46b7e9f764e284df379e
    Patch