Cyber Resilience

CVE-2023-6935

Medium

Published: 09 February 2024

Published
09 February 2024
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 5.9 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS Score 0.0032 55.0th percentile
Risk Priority 12 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2023-6935 is a medium-severity Observable Discrepancy (CWE-203) vulnerability in Wolfssl Wolfssl. Its CVSS base score is 5.9 (Medium).

Operationally, ranked in the top 45.0% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

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…

more

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.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

wolfssl
wolfssl
3.12.2 — 5.6.4

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-203

Misdirection can normalize or falsify responses to eliminate observable discrepancies that aid reconnaissance.

addresses: CWE-203

Observable discrepancies in system behavior can be modulated to create covert storage or timing channels; the required analysis detects and constrains such avenues.

addresses: CWE-203

Prevents attackers from using observable differences in error responses to infer internal system details or state.

References