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CVE-2021-20305

Broken cryptographic algorithm in N/a Nettle

CVSS score

8.1

EPSS probability

%1.7

Risk score

0.1

Published

5 y ago

OverviewPublic Exploits (0)NewsroomVulnerability Timeline
Official patch verified

Etkilenen ürün ve sürüm için yayımlanan güvenlik güncellemesini uygulayın.

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Vulnerability description

DayBreach CVE AI Research

CVE-2021-20305 has vendor, distribution, patch and security-source records on file. We can compare them and prepare an explanation linked to the evidence.

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.

IMPACT: Affected Products and Software

Affected Products

The following products are affected by CVE-2021-20305 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.

IDVENDORPRODUCTACTION
1n/anettle View
2nettle projectnettle View
3fedoraprojectfedora View
4redhatenterprise linux View
5redhatenterprise linux View
6netappactive iq unified manager View
7netappontap select deploy administration utility View
8debiandebian linux View
9debiandebian linux View
Total affected vendors: 6|Products: 9

RED HAT CSAF/VEX: Product Impact Check

Red Hat has not yet published a CSAF/VEX impact record for this CVE. This does not mean “not affected”.

SCORING: CVSS from Multiple Sources

CVSS Scores

The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.

SCOREVERSIONSEVERITYVECTORSOURCE
8.1CVSS V31HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:HNVD
6.8CVSS V2—AV:N/AC:M/Au:N/C:P/I:P/A:PNVD

Patch and Remediation Guide

Solution & Remediation Advisory

Patch verified

1 doğrulanmış yama veya düzeltilmiş sürüm kanıtı bulundu.

nvd

NVD tarafından Patch olarak etiketlenmiş referans

Open source
Confirm the affected product and version against the source evidence above.
Restrict access to internet-facing services and apply network segmentation.
Apply the official update named in the evidence only to the matching product and version.
Monitor server logs and network endpoints for signs of anomalous execution.

Public exploit and active exploitation status

Verified exploit intelligence

No verified public PoC, exploit repository or Metasploit module has been found for this CVE yet.

Weakness Classification and Attack Patterns (CWE & CAPEC)

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-20305 is associated with the following CWEs:

CWE-327: Common Weakness Enumeration Entry CWE-327CWE-787: Out-of-bounds Write

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2021-20305 weaknesses.

CAPEC-66: SQL InjectionCAPEC-126: Path TraversalCAPEC-28: OS Command Injection

Attack Vector and Accessibility

ExposureAğ üzerinden
PermissionsGerekmiyor
UserGerekmiyor

Official Sources and Advisories

https://bugzilla.redhat.com/show_bug.cgi?id=1942533vendor-advisoryGLSA-202105-31vendor-advisoryFEDORA-2021-454a0f6f76vendor-advisoryDSA-4933vendor-advisory[debian-lts-announce] 20210918 [SECURITY] [DLA 2760-1] nettle security updatevendor-advisoryhttps://security.netapp.com/advisory/ntap-20211022-0002/vendor-advisoryhttps://cert-portal.siemens.com/productcert/html/ssa-398330.htmlnvd

CVSS Vector Radar Chart

8.1 / 10
Attack VectorNetworkComplexityHighPrivilegesNoneUser Interact.NoneConfidentialityHighIntegrityNoneAvailabilityHigh

Vulnerability Scoring Details

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack VectorNetwork
Attack ComplexityHigh
Privileges RequiredNone required
User InteractionNone required
Confidentiality (Gizlilik)High
Integrity (Bütünlük)None
Availability (Erişilebilirlik)High

Yama doğrulandı

1 doğrulanmış yama veya düzeltilmiş sürüm kanıtı bulundu.

Follow the vendor

N
n/a logo
n/a
NP
nettle project logo
nettle project
F
fedoraproject logo
fedoraproject
R
redhat logo
redhat
N
netapp logo
netapp
D
debian logo
debian

Weakness Type (CWE & CAPEC)

CWE-327 CWE-787

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