RHSA-2021:1608 - Security Advisory

Topic

An update for python-cryptography is now available for Red Hat Enterprise Linux 8.

Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

Description

The python-cryptography packages contain a Python Cryptographic Authority's (PyCA's) cryptography library, which provides cryptographic primitives and recipes to Python developers.

The following packages have been upgraded to a later upstream version: python-cryptography (3.2.1). (BZ#1873581, BZ#1891947)

Security Fix(es):

• python-cryptography: bleichenbacher timing oracle attack against RSA decryption (CVE-2020-25659)
• python-cryptography: certain sequences of update() calls when symmetrically encrypting very large payloads could result in an integer overflow and lead to buffer overflows (CVE-2020-36242)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Additional Changes:

For detailed information on changes in this release, see the Red Hat Enterprise Linux 8.4 Release Notes linked from the References section.

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

Affected Products

• Red Hat Enterprise Linux for x86_64 8 x86_64
• Red Hat Enterprise Linux for IBM z Systems 8 s390x
• Red Hat Enterprise Linux for Power, little endian 8 ppc64le
• Red Hat Enterprise Linux for ARM 64 8 aarch64

Fixes

• BZ - 1778939 - internal pyca error with X25519, FIPS
• BZ - 1873581 - Rebase python-cryptography to 2.6+ for ed25519 support
• BZ - 1889988 - CVE-2020-25659 python-cryptography: bleichenbacher timing oracle attack against RSA decryption
• BZ - 1891947 - Rebase internal component python-cryptography-vectors
• BZ - 1907429 - Re-add NPN bindings for PyOpenSSL
• BZ - 1926226 - CVE-2020-36242 python-cryptography: certain sequences of update() calls when symmetrically encrypting very large payloads could result in an integer overflow and lead to buffer overflows

CVEs

• CVE-2020-25659
• CVE-2020-36242

References

• https://access.redhat.com/security/updates/classification/#moderate
• https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8/html/8.4_release_notes/