CVE-2020-26521 - Vulnerability Details - OpenCVE

Description

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

Published: 2020-11-06

Score: 7.5 High

EPSS: 2.2% Low

KEV: No

Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

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.

Additional remediation guidance may be available on OpenCVE Cloud.

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

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.

The EPSS score is 0.02157.

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

MITRE

Status: PUBLISHED

Assigner: mitre

Published: 2020-11-06T07:35:12.000Z

Updated: 2024-08-04T15:56:04.653Z

Reserved: 2020-10-02T00:00:00.000Z

Link: CVE-2020-26521

Vulnrichment

No data.

NVD

Status : Modified

Published: 2020-11-06T08:15:13.563

Modified: 2026-06-17T03:08:08.270

Link: CVE-2020-26521

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-476
NULL Pointer Dereference

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