Description
If a TLS 1.3 client gets neither a PSK (pre shared key) extension nor a KSE (key share extension) when connecting to a malicious server, a default predictable buffer gets used for the IKM (Input Keying Material) value when generating the session master secret. Using a potentially known IKM value when generating the session master secret key compromises the key generated, allowing an eavesdropper to reconstruct it and potentially allowing access to or meddling with message contents in the session. This issue does not affect client validation of connected servers, nor expose private key information, but could result in an insecure TLS 1.3 session when not controlling both sides of the connection. wolfSSL recommends that TLS 1.3 client side users update the version of wolfSSL used.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| wolfSSL | wolfSSL | 3.14.0 – ≤ 5.6.0 | — |
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 | 5.5.4-2.1 | — |
| Debian 12 | wolfssl | 5.5.4-2+deb12u1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | wolfssl | No fix yet | — |
| Ubuntu 26.04 LTS | wolfssl | No fix yet | — |
| Ubuntu 25.10 | wolfssl | No fix yet | — |
| Ubuntu 24.04 LTS | wolfssl | No fix yet | — |
| Ubuntu 22.04 LTS | wolfssl | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | wolfssl | No fix yet | — |
| Ubuntu 18.04 LTS | wolfssl | No fix yet | — |
| Ubuntu 16.04 LTS | wolfssl | No fix yet | — |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | wolfssl | 5.6.2-r0 | — |
| Alpine v3.23 | wolfssl | 5.6.2-r0 | — |
| Alpine v3.22 | wolfssl | 5.6.2-r0 | — |
| Alpine v3.21 | wolfssl | 5.6.2-r0 | — |
| Alpine v3.20 | wolfssl | 5.6.2-r0 | — |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | wolfssl | 5.6.2-r0 | — |
| Alpine v3.18 | wolfssl | 5.6.2-r0 | — |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 2 (CBL-Mariner) | mariadb | 10.6.9-3.cm2 | — |