Improper input validation in Wolfssl
CVE-2023-6937
wolfSSL prior to 5.6.6 did not check that messages in one (D)TLS record do not span key boundaries. As a result, it was possible to combine (D)TLS messages using different keys into one (D)TLS record. The most extreme edge case is that, in (D)TLS 1.3, it was possible that an unencrypted (D)TLS 1.3 record from the server containing first a ServerHello message and then the rest of the first server flight would be accepted by a wolfSSL client. In (D)TLS 1.3 the handshake is encrypted after the ServerHello but a wolfSSL client would accept an unencrypted flight from the server. This does not compromise key negotiation and authentication so it is assigned a low severity rating.
Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.
EPSS exploit prediction
EPSS: 0.005 (41.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 41st percentile — 41.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000
Affected products
- Wolfssl — versions 0
Weakness classification (CWE)
Public proof-of-concept exploits
References
- github.com/wolfSSL/wolfssl/pull/7029 (Patch, patch, Issue Tracking)
- www.wolfssl.com/docs/security-vulnerabilities/ (vendor-advisory, Vendor Advisory)
Frequently asked questions
- What is CVE-2023-6937?
- CVE-2023-6937 is a medium-severity vulnerability in Wolfssl, classified under Improper Input Validation. CVSS score: 5.3/10. Published 2024-02-15.
- How severe is CVE-2023-6937?
- Medium severity. CVSS v3 base score is 5.3 out of 10.
- Is CVE-2023-6937 known to be exploited?
- 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.