CVE-2015-7744
CVE-2015-7744 is a medium-severity vulnerability in Wolfssl with a CVSS 3.x base score of 5.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.
Key facts
- Severity: Medium (CVSS 3.x base score 5.9)
- CVSS v2: 2.6
- EPSS exploit prediction: 5% (91st percentile)
- Actively exploited: Not listed in CISA KEV
- Affected product: Wolfssl
- Published:
- Last modified:
Description
wolfSSL (formerly CyaSSL) before 3.6.8 does not properly handle faults associated with the Chinese Remainder Theorem (CRT) process when allowing ephemeral key exchange without low memory optimizations on a server, which makes it easier for remote attackers to obtain private RSA keys by capturing TLS handshakes, aka a Lenstra attack.
Frequently asked questions
- What is CVE-2015-7744?
- wolfSSL (formerly CyaSSL) before 3.6.8 does not properly handle faults associated with the Chinese Remainder Theorem (CRT) process when allowing ephemeral key exchange without low memory optimizations on a server, which makes it easier for remote attackers to obtain private RSA keys by capturing TLS handshakes, aka a Lenstra attack.
- How severe is CVE-2015-7744?
- CVE-2015-7744 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
- Is CVE-2015-7744 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2015-7744?
- CVE-2015-7744 primarily affects Wolfssl. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2015-7744?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2015-7744 published?
- CVE-2015-7744 was published on 2016-01-22 and last updated on 2026-06-17.
References
- http://lists.opensuse.org/opensuse-security-announce/2016-02/msg00015.html
- http://lists.opensuse.org/opensuse-security-announce/2016-02/msg00016.html
- http://wolfssl.com/wolfSSL/Docs-wolfssl-changelog.html
- http://www.oracle.com/technetwork/topics/security/bulletinapr2016-2952098.html
- http://www.oracle.com/technetwork/topics/security/cpujan2016-2367955.html
- http://www.securitytracker.com/id/1034708
- https://people.redhat.com/~fweimer/rsa-crt-leaks.pdf
- https://securityblog.redhat.com/2015/09/02/factoring-rsa-keys-with-tls-perfect-forward-secrecy/
- https://wolfssl.com/wolfSSL/Blog/Entries/2015/9/17_Two_Vulnerabilities_Recently_Found%2C_An_Attack_on_RSA_using_CRT_and_DoS_Vulnerability_With_DTLS.html
Affected products (5)
- cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*
- cpe:2.3:o:opensuse:leap:42.1:*:*:*:*:*:*:*
- cpe:2.3:o:opensuse:opensuse:13.1:*:*:*:*:*:*:*
- cpe:2.3:o:opensuse:opensuse:13.2:*:*:*:*:*:*:*
- cpe:2.3:a:mariadb:mariadb:*:*:*:*:*:*:*:*
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