Description
Mbed TLS before 2.28.10 and 3.x before 3.6.3, on the client side, accepts servers that have trusted certificates for arbitrary hostnames unless the TLS client application calls mbedtls_ssl_set_hostname.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Mbed | mbedtls | < 2.28.10, 3.0.0 – < 3.6.3 | 2.28.10 |
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 14 | mbedtls | 3.6.3-1 | — |
| Debian 13 | mbedtls | 3.6.3-1 | — |
| Debian 12 | mbedtls | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 25.10 | mbedtls | No fix yet | — |
| Ubuntu 24.04 LTS | mbedtls | No fix yet | — |
| Ubuntu 22.04 LTS | mbedtls | No fix yet | — |
| Ubuntu 16.04 LTS | mbedtls | No fix yet | — |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | mbedtls | No fix yet | — |
| Ubuntu Pro 18.04 LTS | mbedtls | No fix yet | — |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | mbedtls-2 | 2.28.10-1.1 | openSUSE-SU-2025:14928-1 |
| openSUSE Leap 16.0 | mbedtls | 3.6.6-bp160.1.1 | openSUSE-SU-2026:21144-1 |
| openSUSE Leap 16.0 | mbedtls-2 | 2.28.10-bp160.1.1 | openSUSE-SU-2026:21145-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | mbedtls +1 | 3.6.3-r0 | — |
| Alpine v3.24 | mbedtls2 | 2.28.10-r0 | — |
| Alpine v3.23 | mbedtls | 3.6.3-r0 | — |
| Alpine v3.23 | mbedtls2 | 2.28.10-r0 | — |
| Alpine v3.22 | mbedtls | 3.6.3-r0 | — |
| Alpine v3.22 | mbedtls2 | 2.28.10-r0 | — |
| Alpine v3.21 | mbedtls | 3.6.3-r0 | — |
| Alpine v3.21 | mbedtls2 | 2.28.10-r0 | — |
| Alpine v3.20 | mbedtls | 3.6.3-r0 | — |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | mbedtls | 2.28.10-r0 | — |
| Alpine v3.18 | mbedtls | 2.28.10-r0 | — |
Advisories 3
- openSUSE-SU-2026:21144-1 Security update for mbedtls SUSE / openSUSE Security Updates · Jun 30, 2026
- openSUSE-SU-2026:21145-1 Security update for mbedtls-2 SUSE / openSUSE Security Updates · Jun 30, 2026
- openSUSE-SU-2025:14928-1 libmbedcrypto7-2.28.10-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026