Description
An issue was discovered in Mbed TLS before 2.24.0 (and before 2.16.8 LTS and before 2.7.17 LTS). There is missing zeroization of plaintext buffers in mbedtls_ssl_read to erase unused application data from memory.
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 | 2.16.9-0.1 | — |
| Debian 13 | mbedtls | 2.16.9-0.1 | — |
| Debian 12 | mbedtls | 2.16.9-0.1 | — |
| Debian 10 | mbedtls | 2.16.9-0~deb10u1 | DLA-3249-1 |
| Debian 9 | mbedtls | 2.4.2-1+deb9u4 | DLA-2826-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| 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 | — |
Advisories 2
- DLA-3249-1 mbedtls - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-2826-1 mbedtls - security update Debian Security (DSA / DLA) · Mar 9, 2026
References
- https://github.com/ARMmbed/mbedtls/releases/tag/v2.7.17
- https://github.com/ARMmbed/mbedtls/releases/tag/v2.16.8
- https://github.com/ARMmbed/mbedtls/releases/tag/v2.24.0
- [debian-lts-announce] 20211123 [SECURITY] [DLA 2826-1] mbedtls security update mailing-list
- [debian-lts-announce] 20221225 [SECURITY] [DLA 3249-1] mbedtls security update mailing-list