vulnerability
F5: CVE-2021-20305: K33101555: Nettle cryptography library vulnerability CVE-2021-20305
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 7 | (AV:N/AC:M/Au:N/C:P/I:P/A:P) | Jun 8, 2021 | Jun 17, 2026 | Jun 17, 2026 |
Severity
7
CVSS
(AV:N/AC:M/Au:N/C:P/I:P/A:P)
Published
Jun 8, 2021
Added
Jun 17, 2026
Modified
Jun 17, 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.
Solution
f5-bigip-upgrade-latest
Rapid7 Labs
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