CVE-2021-20305
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
Exploitability
AV:NAttack VectorNetwork
AC:HAttack ComplexityHigh
PR:NPrivileges RequiredNone
UI:NUser InteractionNone
Scope
S:UScopeUnchanged
Impact
C:HConfidentialityHigh
I:HIntegrityHigh
A:HAvailabilityHigh
Weaknesses
Affected Products
netapp
commercial·US
Nettle Project
oss-projectaka nettle
fedoraproject
oss-project·USaka fedora project
Red Hat Inc.
commercial·USaka redhat, red hat
debian
oss-project·GBaka debian gnu/linux
Canonical Ltd.
commercial·GBaka canonical
and 9 more affected products View all →
Exploitability
Official Patch Available
Attack Graph
Products CVE Techniques Tactics
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MITRE ATT&CK
3 techniques Collection
Initial Access
Privilege Escalation
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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