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.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 13 | wolfssl | 3.9.10+dfsg-1 | — |
| Debian 12 | wolfssl | 3.9.10+dfsg-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | percona-server-5.6 | No fix yet | — |
| Ubuntu 16.04 LTS | percona-xtradb-cluster-5.6 | 5.6.34-26.19-0ubuntu0.16.04.1 | — |
| Ubuntu 14.04 LTS | mariadb-5.5 | 5.5.46-1ubuntu0.14.04.2 | — |
| Ubuntu 14.04 LTS | mysql-5.5 | 5.5.46-0ubuntu0.14.04.2 | — |
| Ubuntu 14.04 LTS | mysql-5.6 | 5.6.27-0ubuntu0.14.04.1 | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP1 | mariadb104 | 10.4.30-150100.3.5.10 | SUSE-RU-2023:3956-1 |
| SLES 15 SP1 | python-mysqlclient | 1.4.6-150100.3.3.7 | SUSE-RU-2023:3956-1 |
| SLES 12 SP5 | lz4 | 1.8.0-3.5.2 | SUSE-RU-2023:4991-1 |
| SLES 12 SP5 | mariadb-connector-c | 3.1.22-2.35.1 | SUSE-RU-2023:4991-1 |
| SLES 12 SP5 | mariadb104 | 10.4.30-8.5.46 | SUSE-RU-2023:4991-1 |
| SLES 12 SP5 | python-mysqlclient | 1.3.14-8.9.2 | SUSE-RU-2023:4991-1 |
| SLES 11 SP4 | mysql | 5.5.47-0.17.1 | SUSE-SU-2016:0348-1 |
| SLES 11 SP3 | mysql | 5.5.47-0.17.1 | SUSE-SU-2016:0348-1 |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 15 SP1 | mariadb104 | 10.4.30-150100.3.5.10 | SUSE-RU-2023:3956-1 |
| SLES for SAP 15 SP1 | python-mysqlclient | 1.4.6-150100.3.3.7 | SUSE-RU-2023:3956-1 |
| SLES for SAP 12 SP5 | lz4 | 1.8.0-3.5.2 | SUSE-RU-2023:4991-1 |
| SLES for SAP 12 SP5 | mariadb-connector-c | 3.1.22-2.35.1 | SUSE-RU-2023:4991-1 |
| SLES for SAP 12 SP5 | mariadb104 | 10.4.30-8.5.46 | SUSE-RU-2023:4991-1 |
| SLES for SAP 12 SP5 | python-mysqlclient | 1.3.14-8.9.2 | SUSE-RU-2023:4991-1 |
| SLES for SAP 11 SP4 | mysql | 5.5.47-0.17.1 | SUSE-SU-2016:0348-1 |
| SLES for SAP 11 SP3 | mysql | 5.5.47-0.17.1 | SUSE-SU-2016:0348-1 |
| SLE HPC 15 SP1 | mariadb104 | 10.4.30-150100.3.5.10 | SUSE-RU-2023:3956-1 |
| SLE HPC 15 SP1 | python-mysqlclient | 1.4.6-150100.3.3.7 | SUSE-RU-2023:3956-1 |
Advisories 4
- SUSE-SU-2016:0348-1 Security update for mysql SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-RU-2023:4991-1 Recommended update for mariadb104 SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-RU-2023:3956-1 Recommended update for mariadb104 SUSE / openSUSE Security Updates · Feb 4, 2026
- WID-SEC-2024-1482 Oracle MySQL: Mehrere Schwachstellen gefährden die Integrität, Vertraulichkeit und Verfügbarkeit BSI CERT-Bund (WID) · Jun 30, 2024
References
- openSUSE-SU-2016:0367 vendor-advisory
- 1034708 vdb-entry
- http://wolfssl.com/wolfSSL/Docs-wolfssl-changelog.html
- https://people.redhat.com/~fweimer/rsa-crt-leaks.pdf
- http://www.oracle.com/technetwork/topics/security/cpujan2016-2367955.html
- http://www.oracle.com/technetwork/topics/security/bulletinapr2016-2952098.html
- 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
- https://securityblog.redhat.com/2015/09/02/factoring-rsa-keys-with-tls-perfect-forward-secrecy/
- openSUSE-SU-2016:0377 vendor-advisory