vulnerability

Red Hat: CVE-2021-20305: CVE-2021-20305 nettle: Out of bounds memory access in signature verification (Multiple Advisories)

Severity
7
CVSS
(AV:N/AC:M/Au:N/C:P/I:P/A:P)
Published
Apr 5, 2021
Added
Apr 9, 2021
Modified
Aug 11, 2025

Description

A flaw was found in Nettle in versions before 3.7.2, 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.

Solutions

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