CVE-2020-26521

View on CVE.org

Published Nov 6, 2020 CVSS 3.1 · 7.5 High EPSS 2.2% KEV · Not listed

Description

The JWT library in NATS nats-server before 2.1.9 allows a denial of service (a nil dereference in Go code).

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

n/a

n/a

affected

Version	Status	Constraints
`n/a`	affected	—

Configuration 1 [-]

cpe:2.3:a:linuxfoundation:nats-server:*:*:*:*:*:*:*:*

Configuration 2 [-]

cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*

No data.

No data available yet.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

Source	ID	Title
EUVD	EUVD-2022-1028	Nil dereference in NATS JWT, DoS of nats-server
Github GHSA	GHSA-h2fg-54x9-5qhq	Nil dereference in NATS JWT, DoS of nats-server

Metrics

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

Access Vector Network

Access Complexity Low

Authentication None

Confidentiality Impact None

Integrity Impact None

Availability Impact Partial

This CVE is not in the KEV list.

Exploit prediction score: 2.2% (2.157% probability within 30 days)

Key SSVC decision points have not yet been added.

References

Link	Providers
http://www.openwall.com/lists/oss-security/2020/11/02/2
https://github.com/nats-io/nats-server/commits/master
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VT67XCLIIBYRT762SVFBYFFTQFVSM3SI/

History

No history.

Subscriptions

Fedoraproject Fedora

Linuxfoundation Nats-server

Weaknesses

CWE-476

Sources

CVE record Updated: Aug 4, 2024, 3:56 PM

Status: PUBLISHED
Assigner: mitre
Published: Nov 6, 2020, 7:35 AM
Updated: Aug 4, 2024, 3:56 PM
Reserved: Oct 2, 2020, 12:00 AM

View source JSON

Vulnrichment No data

No data.

NVD Updated: Jun 17, 2026, 3:08 AM

Status: Modified
Published: Nov 6, 2020, 8:15 AM
Modified: Jun 17, 2026, 3:08 AM

View source JSON

Red Hat No data

No data.

OpenCVE enrichment No data

No data.

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