ALAS2-2021-1629

Amazon Linux 2 Security Advisory: ALAS-2021-1629
Advisory Release Date: 2021-04-20 17:55 Pacific
Advisory Updated Date: 2021-04-21 17:57 Pacific
Severity: Important
Issue Overview:

A flaw was found in Nettle, where several Nettle signature verification functions (GOST DSA, EDDSA & ECDSA) result in the Elliptic Curve Cryptography point (ECC) multiply function being called with out-of-range scalers, possibly resulting in incorrect results. This flaw allows an attacker to force an invalid signature, causing an assertion failure or possible validation. The highest threat to this vulnerability is to confidentiality, integrity, as well as system availability. (CVE-2021-20305)


Affected Packages:

nettle


Note:

This advisory is applicable to Amazon Linux 2 (AL2) Core repository. Visit this FAQ section for the difference between AL2 Core and AL2 Extras advisories.


Issue Correction:
Run yum update nettle to update your system.

New Packages:
aarch64:
    nettle-2.7.1-9.amzn2.aarch64
    nettle-devel-2.7.1-9.amzn2.aarch64
    nettle-debuginfo-2.7.1-9.amzn2.aarch64

i686:
    nettle-2.7.1-9.amzn2.i686
    nettle-devel-2.7.1-9.amzn2.i686
    nettle-debuginfo-2.7.1-9.amzn2.i686

src:
    nettle-2.7.1-9.amzn2.src

x86_64:
    nettle-2.7.1-9.amzn2.x86_64
    nettle-devel-2.7.1-9.amzn2.x86_64
    nettle-debuginfo-2.7.1-9.amzn2.x86_64

Additional References

Red Hat: CVE-2021-20305

Mitre: CVE-2021-20305