Mageia 2020-0469: mbedtls security update

This update provides security bug fixes and minor enhancements. Limit the size of calculations performed by mbedtls_mpi_exp_mod to MBEDTLS_MPI_MAX_SIZE to prevent a potential denial of service when generating Diffie-Hellman key pairs.

MGASA-2020-0469 - Updated mbedtls packages fix security vulnerabilities

Publication date: 21 Dec 2020
URL: https://advisories.mageia.org/MGASA-2020-0469.html
Type: security
Affected Mageia releases: 7

This update provides security bug fixes and minor enhancements.

Limit the size of calculations performed by mbedtls_mpi_exp_mod to
MBEDTLS_MPI_MAX_SIZE to prevent a potential denial of service when generating
Diffie-Hellman key pairs.

A failure of the random generator was ignored in mbedtls_mpi_fill_random(),
which is how most uses of randomization in asymmetric cryptography are
implemented. This could cause failures or the silent use of non-random values. 

Fix a compliance issue whereby the library did not check the tag on the
algorithm parameters (only the size) when comparing the signature in the
description part of the cert to the real signature.

Zeroising of local buffers and variables which are used for calculations in
mbedtls_pkcs5_pbkdf2_hmac(), mbedtls_internal_sha*_process(),
mbedtls_internal_md*_process() and mbedtls_internal_ripemd160_process()
functions to erase sensitive data from memory.

References:
- https://bugs.mageia.org/show_bug.cgi?id=27869
- https://github.com/ARMmbed/mbedtls/releases/tag/v2.16.9

SRPMS:
- 7/core/mbedtls-2.16.9-1.mga7