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CVE-2021-20305

Published: Apr 5, 2021Updated: Nov 21, 2024 Sources: CVE List NVD BDU csafCWE-327
8.1HIGH
NVD MITRE
EPSS Score
1.6%
Top 26.2%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

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.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:HPR:NUI:NS:UC:HI:HA:H
Exploitability
AV:NAttack Vector
Network
AC:HAttack Complexity
High
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:HAvailability
High
Open in CVSS calculator →

Weaknesses

CWE-327CWE-787

Affected Products

netapp
commercial·US
active iq unified manager
Hardware Firmware
ontap select deploy administration utility
Hardware Firmware
Nettle Project
oss-projectaka nettle
NettleLibrary
OSS Libraries / generic-library
fedoraproject
oss-project·USaka fedora project
fedoraOn-premOS
Operating Systems / linux-distro
Red Hat Inc.
commercial·USaka redhat, red hat
Red Hat Enterprise LinuxOn-premOS
Operating Systems / linux-distro
debian
oss-project·GBaka debian gnu/linux
debian linuxOn-premOS
Operating Systems / linux-distro
Canonical Ltd.
commercial·GBaka canonical
UbuntuOn-premOS
Operating Systems / linux-distro
and 9 more affected products View all →

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

Click technique nodes for MITRE ATT&CK details · drag to pan · Ctrl/⌘ + scroll to zoom, or go fullscreen.

MITRE ATT&CK

3 techniques
Collection
Initial Access
Privilege Escalation
View detailed technique mapping

References

https://bugzilla.redhat.com/show_bug.cgi?id=1942533
bugzilla.redhat.com
https://lists.debian.org/debian-lts-announce/2021/09/msg00008.html
lists.debian.org
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/MQKWVVMAIDAJ7YAA3VVO32BHLDOH2E63/
lists.fedoraproject.org
and 25 more references View all →

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