Nginx < 1.20.1 Off-By-One Heap Write

critical Web Application Scanning Plugin ID 112796
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Synopsis

Nginx < 1.20.1 Off-By-One Heap Write

Description

According to its self-reported version number, the detected version of nginx is prior to 1.20.1. It is, therefore, affected by an off-by-one error in ngx_resolver_copy() while processing DNS responses.

Note that the scanner has not tested for these issues but has instead relied only on the application's self-reported version number.

Solution

Upgrade to nginx version 1.20.1 or later.

See Also

http://mailman.nginx.org/pipermail/nginx-announce/2021/000300.html

https://www.x41-dsec.de/lab/advisories/x41-2021-002-nginx-resolver-copy/

Plugin Details

Severity: Critical

ID: 112796

Type: remote

Published: 5/26/2021

Updated: 10/15/2021

Scan Template: scan, pci, api

Risk Information

CVSS Score Source: CVE-2021-23017

CVSS v2

Risk Factor: Medium

Base Score: 6.8

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

CVSS v3

Risk Factor: Critical

Base Score: 9.4

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L

Vulnerability Information

CPE: cpe:2.3:a:nginx:nginx:*:*:*:*:*:*:*:*

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 5/25/2021

Vulnerability Publication Date: 5/25/2021

Reference Information

CVE: CVE-2021-23017