CVE-2023-6935 Marvin Attack vulnerability in SP Math All RSA

2024-02-0922:25:04

CWE-203

wolfSSL

www.cve.org

wolfssl

sp math

rsa

vulnerability

marvin attack

timing attack

bleichenbacher

static cipher suites

decryption

signature forging

padding-independent

cve-2023-6935

5.9 Medium

CVSS3

Attack Vector

NETWORK

Attack Complexity

HIGH

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

HIGH

Integrity Impact

NONE

Availability Impact

NONE

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

0.0004 Low

EPSS

Percentile

9.2%

JSON

wolfSSL SP Math All RSA implementation is vulnerable to the Marvin Attack, new variation of a timing Bleichenbacher style attack, when built with the following options to configure:

–enable-all CFLAGS=“-DWOLFSSL_STATIC_RSA”

The define “WOLFSSL_STATIC_RSA” enables static RSA cipher suites, which is not recommended, and has been disabled by default since wolfSSL 3.6.6. Therefore the default build since 3.6.6, even with “–enable-all”, is not vulnerable to the Marvin Attack. The vulnerability is specific to static RSA cipher suites, and expected to be padding-independent.

The vulnerability allows an attacker to decrypt ciphertexts and forge signatures after probing with a large number of test observations. However the server’s private key is not exposed.

CNA Affected

[
  {
    "defaultStatus": "unaffected",
    "modules": [
      "RSA"
    ],
    "product": "wolfSSL",
    "repo": "https://github.com/wolfSSL/wolfssl",
    "vendor": "wolfSSL",
    "versions": [
      {
        "lessThanOrEqual": "5.6.4",
        "status": "affected",
        "version": "3.12.2",
        "versionType": "release bundle"
      }
    ]
  }
]