Medium severity · published Feb 9, 2024
CVE-2023-6935
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…
5.9
CVSS
0.5%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 45% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
WO
Wolfssl · Wolfssl
3.12.2 through 5.6.4 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-6935
CVE.org
https://www.cve.org/CVERecord?id=CVE-2023-6935
Technical Description
https://people.redhat.com/~hkario/marvin/
Vendor Advisory
https://www.wolfssl.com/docs/security-vulnerabilities/
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