vulnerability
Ubuntu: USN-4906-1 (CVE-2021-20305): Nettle vulnerability
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 7 | (AV:N/AC:M/Au:N/C:P/I:P/A:P) | Apr 5, 2021 | Apr 14, 2021 | Mar 27, 2026 |
Severity
7
CVSS
(AV:N/AC:M/Au:N/C:P/I:P/A:P)
Published
Apr 5, 2021
Added
Apr 14, 2021
Modified
Mar 27, 2026
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
ubuntu-upgrade-libnettle6ubuntu-upgrade-libnettle7ubuntu-upgrade-libnettle8
Rapid7 Labs
2026 Global Threat Landscape Report
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