CVE-2021-20305

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Summary

CVECVE-2021-20305
StatePUBLISHED
Assignerredhat
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-04-05 22:15:12 UTC
Updated2026-10-14 11:16:51 UTC
DescriptionA 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.

Risk And Classification

Primary CVSS: v3.1 8.1 HIGH from [email protected]

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Problem Types: CWE-327 | CWE-787 | CWE-327 CWE-327

VersionSourceTypeScoreSeverityVector
3.1[email protected]Primary8.1HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
2.0[email protected]Primary6.8AV:N/AC:M/Au:N/C:P/I:P/A:P

CVSS v3.1 Breakdown

Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS v2.0 Breakdown

Access Vector
Network
Access Complexity
Medium
Authentication
None
Confidentiality
Partial
Integrity
Partial
Availability
Partial

AV:N/AC:M/Au:N/C:P/I:P/A:P

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Operating System Debian Debian Linux 10.0 All All All
Operating System Debian Debian Linux 9.0 All All All
Operating System Fedoraproject Fedora 33 All All All
Application Netapp Active Iq Unified Manager - All All All
Application Netapp Ontap Select Deploy Administration Utility - All All All
Application Nettle Project Nettle All All All All
Operating System Redhat Enterprise Linux 7.0 All All All
Operating System Redhat Enterprise Linux 8.0 All All All

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA Na Nettle affected nettle 3.7.2 Not specified
ADP Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP affected V3.1.0 V3.1.5 custom Not specified
ADP Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP affected V3.1.0 V3.1.5 custom Not specified
ADP Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP affected V3.1.0 V3.1.5 custom Not specified
ADP Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP affected V3.1.0 V3.1.5 custom Not specified
ADP Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP affected V3.1.0 V3.1.5 custom Not specified

References

ReferenceSourceLinkTags
cert-portal.siemens.com/productcert/html/ssa-398330.html 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e cert-portal.siemens.com
1942533 – (CVE-2021-20305) CVE-2021-20305 nettle: Out of Bound memory access in signature verification af854a3a-2127-422b-91ae-364da2661108 bugzilla.redhat.com Issue Tracking, Patch, Third Party Advisory
[SECURITY] Fedora 33 Update: gnutls-3.6.16-1.fc33 - package-announce - Fedora Mailing-Lists af854a3a-2127-422b-91ae-364da2661108 lists.fedoraproject.org
CVE-2021-20305 Nettle Vulnerability in NetApp Products | NetApp Product Security af854a3a-2127-422b-91ae-364da2661108 security.netapp.com Third Party Advisory
Debian -- Security Information -- DSA-4933-1 nettle af854a3a-2127-422b-91ae-364da2661108 www.debian.org Third Party Advisory
[SECURITY] [DLA 2760-1] nettle security update af854a3a-2127-422b-91ae-364da2661108 lists.debian.org Mailing List, Third Party Advisory
Nettle: Denial of service (GLSA 202105-31) — Gentoo security af854a3a-2127-422b-91ae-364da2661108 security.gentoo.org Third Party Advisory
[SECURITY] Fedora 33 Update: gnutls-3.6.16-1.fc33 - package-announce - Fedora Mailing-Lists MITRE lists.fedoraproject.org
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Legacy QID Mappings

  • 159146 Oracle Enterprise Linux Security Update for nettle (ELSA-2021-1145)
  • 159150 Oracle Enterprise Linux Security Update for gnutls and nettle (ELSA-2021-1206)
  • 174949 SUSE Enterprise Linux Security Update for libnettle (SUSE-SU-2021:1399-1)
  • 174959 SUSE Enterprise Linux Security Update for libnettle (SUSE-SU-2021:1412-1)
  • 178677 Debian Security Update for nettle (DSA 4933-1)
  • 178806 Debian Security Update for nettle (DLA 2760-1)
  • 179505 Debian Security Update for nettle (CVE-2021-20305)
  • 198322 Ubuntu Security Notification for Nettle vulnerability (USN-4906-1)
  • 239215 Red Hat Update for nettle (RHSA-2021:1145)
  • 239220 Red Hat Update for gnutls and nettle (RHSA-2021:1206)
  • 239241 Red Hat Update for gnutls and nettle (RHSA-2021:1246)
  • 239242 Red Hat Update for gnutls and nettle (RHSA-2021:1245)
  • 239414 Red Hat Update for nettle (RHSA-2021:2280)
  • 257076 CentOS Security Update for nettle (CESA-2021:1145)
  • 281107 Fedora Security Update for gnutls (FEDORA-2021-454a0f6f76)
  • 296059 Oracle Solaris 11.4 Support Repository Update (SRU) 36.0.1.101.2 Missing (CPUJUL2021)
  • 352269 Amazon Linux Security Advisory for nettle: ALAS2-2021-1629
  • 375673 F5 BIG-IP ASM,LTM,APM BIG-IP Nettle Cryptography Library Vulnerability (K33101555)
  • 377030 Alibaba Cloud Linux Security Update for nettle (ALINUX2-SA-2021:0018)
  • 377158 Alibaba Cloud Linux Security Update for gnutls and nettle (ALINUX3-SA-2021:0029)
  • 501441 Alpine Linux Security Update for nettle
  • 504179 Alpine Linux Security Update for nettle
  • 591406 Siemens SIMATIC S7-1500 CPU GNU/Linux subsystem Multiple Vulnerabilities (SSB-439005, ICSA-22-104-13)
  • 670549 EulerOS Security Update for nettle (EulerOS-SA-2021-2307)
  • 670778 EulerOS Security Update for nettle (EulerOS-SA-2021-2536)
  • 670802 EulerOS Security Update for nettle (EulerOS-SA-2021-2560)
  • 710083 Gentoo Linux Nettle Denial of service (GLSA 202105-31)
  • 730121 McAfee Web Gateway Multiple Vulnerabilities (WP-3484,WP-3744,WP-3745,WP-3746,WP-3747,WP-3793,WP-3800)
  • 750241 OpenSUSE Security Update for libnettle (openSUSE-SU-2021:0635-1)
  • 900066 CBL-Mariner Linux Security Update for nettle 3.4.1
  • 903108 Common Base Linux Mariner (CBL-Mariner) Security Update for nettle (4053)
  • 940036 AlmaLinux Security Update for gnutls and nettle (ALSA-2021:1206)
  • 960830 Rocky Linux Security Update for gnutls and nettle (RLSA-2021:1206)

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