Vulnerability Name:

CVE-2020-26521 (CCN-191004)

Assigned:2020-11-02
Published:2020-11-02
Updated:2022-01-01
Summary:The JWT library in NATS nats-server before 2.1.9 allows a denial of service (a nil dereference in Go code).
CVSS v3 Severity:7.5 High (CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
6.5 Medium (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): None
Integrity (I): None
Availibility (A): High
7.5 High (CCN CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
6.5 Medium (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): None
Integrity (I): None
Availibility (A): High
CVSS v2 Severity:5.0 Medium (CVSS v2 Vector: AV:N/AC:L/Au:N/C:N/I:N/A:P)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Low
Authentication (Au): None
Impact Metrics:Confidentiality (C): None
Integrity (I): None
Availibility (A): Partial
7.8 High (CCN CVSS v2 Vector: AV:N/AC:L/Au:N/C:N/I:N/A:C)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Low
Athentication (Au): None
Impact Metrics:Confidentiality (C): None
Integrity (I): None
Availibility (A): Complete
Vulnerability Type:CWE-476
Vulnerability Consequences:Denial of Service
References:Source: MITRE
Type: CNA
CVE-2020-26521

Source: CONFIRM
Type: Mailing List, Third Party Advisory
http://www.openwall.com/lists/oss-security/2020/11/02/2

Source: XF
Type: UNKNOWN
nats-cve202026521-dos(191004)

Source: CCN
Type: jwt GIT Repository
NATS JWT

Source: CCN
Type: nats-server GIT Repository
NATS Server

Source: MISC
Type: Patch, Third Party Advisory
https://github.com/nats-io/nats-server/commits/master

Source: FEDORA
Type: Mailing List, Third Party Advisory
FEDORA-2020-2c8851d48b

Source: CCN
Type: oss-sec Mailing List, Mon, 19 Oct 2020 20:00:21 +0800 (CST)
[CVE-2020-26521][CVE-2020-26892] NATS JWT vulnerabilities

Vulnerable Configuration:Configuration 1:
  • cpe:/a:linuxfoundation:nats-server:*:*:*:*:*:*:*:* (Version < 2.1.9)

  • Configuration 2:
  • cpe:/o:fedoraproject:fedora:33:*:*:*:*:*:*:*

  • * Denotes that component is vulnerable
    BACK
    linuxfoundation nats-server *
    fedoraproject fedora 33